prototype inclusion of release notes in docs

 * Treat them as a top level "type" of doc
 * Sidebar sorting is finicky :-/
 * Some friction around when we write the notes versus switch the
 'current' doc version

ref pantsbuild#89

docs/notes/2.1.x.md

@@ -0,0 +1,233 @@
+# 2.1.x Stable Releases
+
+This document describes releases leading up to the `2.1.x` `stable`
+series.
+
+See <https://www.pantsbuild.org/v2.1/docs/release-notes-2-1> for an
+overview of the changes in this release.
+
+## 2.1.2 (2/9/2020)
+
+The third stable release in the 2.1.x series, with no changes since
+`2.1.2rc0`.
+
+## 2.1.2rc0 (2/4/2021)
+
+### Bugfixes
+
+-   Fix older versions of `tar` not working when creating an
+    `archive` (Cherry-pick of #11413) ([#11418](https://github.com/pantsbuild/pants/pull/11418))
+
+## 2.1.1 (12/18/2020)
+
+The second stable release in the 2.1.x series, with no changes since
+`rc2`.
+
+Thank you to everyone who helped test the rcs!
+
+## 2.1.1rc2 (12/16/2020)
+
+### Bugfixes
+
+-   Fix filtering of log messages generated in native code. (cherrypick
+    of #11313) ([#11316](https://github.com/pantsbuild/pants/pull/11316))
+-   Upgrade to Pex 2.1.24. (cherrypick of #11312) ([#11315](https://github.com/pantsbuild/pants/pull/11315))
+-   Clean the graph speculatively, and cancel nodes when interest is
+    lost (cherrypick of #11308) ([#11311](https://github.com/pantsbuild/pants/pull/11311))
+-   Implement native Process cache scoping to fix --test-force
+    (cherrypick of #11291) ([#11298](https://github.com/pantsbuild/pants/pull/11298))
+-   Increase Pants' python recursion limit by default, and allow it to
+    be overridden. (cherrypick of #11271) ([#11274](https://github.com/pantsbuild/pants/pull/11274))
+-   Revert "Move graph cycle detection to rust. (#11202)" (cherrypick
+    of #11272) ([#11275](https://github.com/pantsbuild/pants/pull/11202)) [PR
+    #11275](https://github.com/pantsbuild/pants/pull/11275)
+
+## 2.1.1rc1 (11/24/2020)
+
+### Bugfixes
+
+-   Fix off-by-one error for `python_awslambda`
+    `sources` field validation ([#11234](https://github.com/pantsbuild/pants/pull/11234))
+-   Remove extraneous INFO level log line (Cherry-pick of #11228)
+    ([#11229](https://github.com/pantsbuild/pants/pull/11229))
+
+## 2.1.1rc0 (11/20/2020)
+
+### User API Changes
+
+-   Revert premature deprecation of `sources` field for
+    `python_awslambda` ([#11217](https://github.com/pantsbuild/pants/pull/11217))
+
+### Bugfixes
+
+-   Move graph cycle detection to Rust to fix recursion limit.
+    (cherrypick of #11202) ([#11204](https://github.com/pantsbuild/pants/pull/11204))
+-   Set the soft ulimit value more conservatively to fix macOS Big Sur
+    issue (cherrypick of #11194) ([#11197](https://github.com/pantsbuild/pants/pull/11197))
+
+## 2.1.0 (11/17/2020)
+
+The first stable release of the `2.1.x` series, with no changes since
+the previous release candidate.
+
+## 2.1.0rc3 (11/16/2020)
+
+### Bugfixes
+
+-   Fix relative imports in dependency inference (Cherry-pick of #11181)
+    ([#11189](https://github.com/pantsbuild/pants/pull/11189))
+
+## 2.1.0rc2 (11/13/2020)
+
+### New Features
+
+-   Remoting: allow timeout parameters to be configured (Cherry-pick of
+    #11125) ([#11158](https://github.com/pantsbuild/pants/pull/11158))
+
+### User API Changes
+
+-   Deprecate running Pants with Python 3.6 ([#11173](https://github.com/pantsbuild/pants/pull/11173))
+-   Deprecate the `sources` field for
+    `python_awslambda` (Cherry-pick of #11176) ([#11178](https://github.com/pantsbuild/pants/pull/11178))
+
+### Bugfixes
+
+-   make a few minor reliability fixes to remote caching code
+    (Cherry-pick of #11130) ([#11159](https://github.com/pantsbuild/pants/pull/11159))
+
+## 2.1.0rc1 (11/11/2020)
+
+### Bugfixes
+
+-   Upgrade to Pex 2.1.21 (Cherry-pick of #11131) ([#11134](https://github.com/pantsbuild/pants/pull/11134))
+-   Fix Coverage not finding resource files when generating a report
+    (Cherry-pick of #11129) ([#11138](https://github.com/pantsbuild/pants/pull/11138))
+
+## 2.1.0rc0 (11/9/2020)
+
+### New Features
+
+-   Add `export-codegen` goal ([#11107](https://github.com/pantsbuild/pants/pull/11107))
+-   Add `./pants py-constraints --summary` for project
+    overview ([#11099](https://github.com/pantsbuild/pants/pull/11099))
+-   Add `./pants help subsystems` ([#11088](https://github.com/pantsbuild/pants/pull/11088))
+-   Improve performance of dependency inference ([#11094](https://github.com/pantsbuild/pants/pull/11094))
+
+### User API Changes
+
+-   Change default for `--pants-distdir-legacy-paths` and
+    deprecate it ([#11096](https://github.com/pantsbuild/pants/pull/11096))
+-   Clarify that process cache namespacing works for all runners
+    ([#11095](https://github.com/pantsbuild/pants/pull/11095))
+-   Deprecate target names containing slashes and colons ([#11115](https://github.com/pantsbuild/pants/pull/11115))
+
+### Plugin API Changes
+
+-   Rename `SourcesSnapshot` to `SpecsSnapshot`
+    ([#11114](https://github.com/pantsbuild/pants/pull/11114))
+
+### Bugfixes
+
+-   Fix logs for `test`, `lint`,
+    `fmt`, and `typecheck` to always print, even
+    if cached ([#11111](https://github.com/pantsbuild/pants/pull/11111))
+-   Fix `pytest.pex` leaking into coverage data ([#11110](https://github.com/pantsbuild/pants/pull/11110))
+-   Fix `--pex-verbosity` to work with the interpreter
+    selection PEX ([#11108](https://github.com/pantsbuild/pants/pull/11108))
+-   Fix `!!` transitive excludes when used multiple times in
+    a repo ([#11103](https://github.com/pantsbuild/pants/pull/11103))
+-   Fix `setup_py.with_provides()` to respect the
+    `:func` entry-point shorthand ([#11093](https://github.com/pantsbuild/pants/pull/11093))
+-   Include a host fingerprint in pantsd's identity ([#11092](https://github.com/pantsbuild/pants/pull/11092))
+
+### Documentation
+
+-   Improve error message for invalid unions in `Get()`s ([#11102](https://github.com/pantsbuild/pants/pull/11102))
+
+## 2.1.0.dev0 (10/30/2020)
+
+### User API Changes
+
+-   Do not error if `./pants package` does not match any
+    targets ([#11051](https://github.com/pantsbuild/pants/pull/11051))
+-   Deprecate the `compatibility` field in favor of
+    `interpreter_constraints` ([#11074](https://github.com/pantsbuild/pants/pull/11074))
+-   Remove deprecated `awslambda`, `binary`, and
+    `setup-py` goals in favor of `package`
+    ([#11048](https://github.com/pantsbuild/pants/pull/11048))
+-   Rename pex-binary/python-distribution to avoid naming collisions.
+    ([#11007](https://github.com/pantsbuild/pants/pull/11007))
+-   Remove deprecated `--{fmt,lint}-per-target-caching` in
+    favor of `--per-file-caching` ([#11062](https://github.com/pantsbuild/pants/pull/11062))
+-   Remove post_stats from RunTracker ([#11068](https://github.com/pantsbuild/pants/pull/11068))
+-   Remove stats_version in runtracker ([#11065](https://github.com/pantsbuild/pants/pull/11065))
+-   Remove deprecated `--lang` and `--lc-all`
+    options in favor of `--env-vars` ([#11066](https://github.com/pantsbuild/pants/pull/11066))
+-   Remove deprecated `--protoc-runtime-targets` option
+    ([#11083](https://github.com/pantsbuild/pants/pull/11083))
+-   Remove deprecated `--interpreter-constraints` option
+    for some Python tools ([#11082](https://github.com/pantsbuild/pants/pull/11082))
+-   Remove deprecated `runtime_binary_dependencies` field
+    ([#11079](https://github.com/pantsbuild/pants/pull/11079))
+-   Remove deprecated `--spec-file` option in favor of
+    `--spec-files` ([#11076](https://github.com/pantsbuild/pants/pull/11076))
+-   Remove deprecated `[basic-auth]`,
+    `[reporter]`, and `run-tracker`
+    options ([#11078](https://github.com/pantsbuild/pants/pull/11078))
+-   Remove deprecated `--print-exception-stacktrace` in
+    favor of `--print-stacktrace` ([#11085](https://github.com/pantsbuild/pants/pull/11085))
+-   Remove unused global options ([#11077](https://github.com/pantsbuild/pants/pull/11077))
+-   Remove deprecated `python_requirement` BUILD file symbol
+    ([#11055](https://github.com/pantsbuild/pants/pull/11055))
+-   Deprecate the `platforms` field allowing a bare string
+    ([#11073](https://github.com/pantsbuild/pants/pull/11073))
+-   Deprecate several unused options ([#11041](https://github.com/pantsbuild/pants/pull/11041))
+-   Deprecate unused `run-tracker` options ([#11038](https://github.com/pantsbuild/pants/pull/11038))
+-   Remove deprecated `python-setup` options ([#10984](https://github.com/pantsbuild/pants/pull/10984))
+-   Remove deprecated `Subsystem.get_options()` in favor of
+    `Subsystem.options` ([#10986](https://github.com/pantsbuild/pants/pull/10986))
+-   Remove deprecated global options like `--v2` and
+    `--backend-packages2` ([#10985](https://github.com/pantsbuild/pants/pull/10985))
+-   Remove deprecated `--changed-*` options ([#10982](https://github.com/pantsbuild/pants/pull/10982))
+-   Remove deprecated `./pants filter` options ([#10983](https://github.com/pantsbuild/pants/pull/10983))
+
+### New Features
+
+-   Add `[python-setup].resolver_http_cache_ttl` option
+    ([#10997](https://github.com/pantsbuild/pants/pull/10997))
+-   Add new `py-constraints` goal through new
+    `pants.backend.python.mixed_interpreter_constraints`
+    backend ([#11075](https://github.com/pantsbuild/pants/pull/11075))
+-   Add `:my_func` shorthand for the
+    `entry_point` field ([#11064](https://github.com/pantsbuild/pants/pull/11064))
+-   Add new EngineAware method metadata() ([#11030](https://github.com/pantsbuild/pants/pull/11030))
+-   remote caching support ([#10960](https://github.com/pantsbuild/pants/pull/10960))
+-   Store per-run logs on RunTracker ([#11025](https://github.com/pantsbuild/pants/pull/11025))
+-   Allow changing the URL to download tools like PEX and Protoc
+    ([#11013](https://github.com/pantsbuild/pants/pull/11013))
+-   Add mechanism to deprecate target types and fields ([#10966](https://github.com/pantsbuild/pants/pull/10966))
+
+### Bugfixes
+
+-   remote caching: upload stdout/stderr content to remote cache
+    ([#11049](https://github.com/pantsbuild/pants/pull/11049))
+-   Fix PEX to always write to `named_caches_dir`, rather
+    than `~/.pex` ([#11040](https://github.com/pantsbuild/pants/pull/11040))
+-   Fix `setup_py().with_binaries()` to use the default
+    entry point ([#11021](https://github.com/pantsbuild/pants/pull/11021))
+-   Fix resource leak warning with stdio ([#10995](https://github.com/pantsbuild/pants/pull/10995))
+-   Fix `./pants repl` to use global constrains when no
+    targets specified ([#10991](https://github.com/pantsbuild/pants/pull/10991))
+-   Fix overly verbose `FieldSet` in stack traces ([#10978](https://github.com/pantsbuild/pants/pull/10978))
+-   Fix several bad usages of `itertools.groupby()` ([#10976](https://github.com/pantsbuild/pants/pull/10976))
+-   Fix bug with linter targets being skipped ([#10974](https://github.com/pantsbuild/pants/pull/10974))
+-   Fix config validation not erroring on global options in wrong scope
+    ([#10950](https://github.com/pantsbuild/pants/pull/10950))
+-   Automatically set setuptools interpreter constraints if unspecified
+    ([#10951](https://github.com/pantsbuild/pants/pull/10951))
+
+### Documentation
+
+-   Improve error message for invalid input in `Get()`s ([#11081](https://github.com/pantsbuild/pants/pull/11081))
+-   Improve several help messages ([#11029](https://github.com/pantsbuild/pants/pull/11029))
+-   Fold target help into the help system. ([#11022](https://github.com/pantsbuild/pants/pull/11022))