[6.1] open source previously enterprise code (#2373)

* move enterprise sources/submodule to OSS repo

* only use gitignore in root

* add license headers to the e subdir

* remote .github from e subdir

.gitignore

@@ -2,6 +2,7 @@
 .vagrant
 .DS_Store
 /build/
+/e/build/
 *.test
 flymake*
 *tar

e/.gitattributes

@@ -0,0 +1,2 @@
+web/dist/* linguist-vendored
+vendor/* linguist-vendored

e/Makefile

@@ -0,0 +1,116 @@
+TOP := $(realpath $(dir $(CURDIR)/$(word $(words $(MAKEFILE_LIST)),$(MAKEFILE_LIST))))
+CURRENT_TAG ?= $(shell cd .. && ./version.sh)
+GRAVITY_TAG := $(CURRENT_TAG)
+# Abbreviated gravity version to use as a build ID
+GRAVITY_VERSION := $(CURRENT_TAG)
+CURRENT_COMMIT := $(shell git rev-parse HEAD)
+VERSION_FLAGS := -X github.com/gravitational/gravity/vendor/github.com/gravitational/version.gitCommit=$(CURRENT_COMMIT) \
+	-X github.com/gravitational/gravity/vendor/github.com/gravitational/version.version=$(GRAVITY_VERSION)
+LINKFLAGS := "$(VERSION_FLAGS) -w -s"
+
+GRAVITY_WEB_APP_DIR := $(TOP)/web
+GRAVITY_PKG_PATH=github.com/gravitational/gravity/e
+ifdef LOCAL
+BUILDDIR=$(TOP)/../build
+GRAVITY_BASE_PKG_PATH=github.com/gravitational/gravity
+LOCAL_BUILDDIR=/gopath/src/$(GRAVITY_BASE_PKG_PATH)/build
+LOCAL_GRAVITY_BUILDDIR=/gopath/src/$(GRAVITY_BASE_PKG_PATH)/build/$(GRAVITY_VERSION)
+else
+BUILDDIR=$(TOP)/build
+LOCAL_BUILDDIR=/gopath/src/$(GRAVITY_PKG_PATH)/build
+LOCAL_GRAVITY_BUILDDIR=/gopath/src/$(GRAVITY_PKG_PATH)/build/$(GRAVITY_VERSION)
+endif
+
+BINARIES ?= gravity tele terraform-provider-gravity terraform-provider-gravityenterprise
+
+GRAVITY_BUILDDIR ?= $(BUILDDIR)/$(GRAVITY_VERSION)
+TEST_PACKAGES ?= \
+	 $(GRAVITY_PKG_PATH)/lib/... \
+	 $(GRAVITY_PKG_PATH)/tool/...
+
+export BUILDDIR \
+	GRAVITY_PKG_PATH \
+	LOCAL_BUILDDIR \
+	LOCAL_GRAVITY_BUILDDIR \
+	GRAVITY_WEB_APP_DIR \
+	BINARIES
+
+.PHONY: build
+build:
+	$(MAKE) -C .. build
+
+.PHONY: version
+version:
+	@echo $(GRAVITY_VERSION)
+
+.PHONY: dev
+dev:
+	$(MAKE) -C .. dev
+
+.PHONY: $(BINARIES)
+$(BINARIES):
+	$(MAKE) -C .. $@
+
+.PHONY: install
+install:
+	$(MAKE) -C .. install
+
+.PHONY: clean
+clean:
+	rm -rf $(BUILDDIR)
+
+.PHONY: production
+production:
+	$(MAKE) -C .. production
+
+.PHONY: telekube
+telekube:
+	$(MAKE) -C .. telekube
+
+.PHONY: wormhole
+wormhole:
+	$(MAKE) -C .. wormhole
+
+.PHONY: opscenter
+opscenter:
+	$(MAKE) -C .. opscenter
+
+.PHONY: site-app
+site-app:
+	$(MAKE) -C .. site-app
+
+.PHONY: telekube-app
+telekube-app:
+	$(MAKE) -C .. telekube-app
+
+.PHONY: test
+test:
+	$(MAKE) TEST_PACKAGES="$(TEST_PACKAGES)" -C .. test
+
+.PHONY: test-package
+test-package:
+	go test -v ./$(p)
+
+.PHONY: publish-telekube
+publish-telekube:
+	$(MAKE) -C .. publish-telekube
+
+.PHONY: publish-artifacts
+publish-artifacts:
+	$(MAKE) -C .. publish-artifacts
+
+.PHONY: publish
+publish:
+	$(MAKE) -C .. publish
+
+.PHONY: robotest-run-suite
+robotest-run-suite:
+	$(MAKE) -C .. robotest-run-suite
+
+.PHONY: robotest-run-nightly
+robotest-run-nightly:
+	$(MAKE) -C .. robotest-run-nightly
+
+.PHONY: goinstall
+goinstall:
+	$(MAKE) -C .. goinstall