Remove generic parameters from Hypercore and Storage

[cowlicks]

This removes the generic parameter from Storage, which in turn removes the generic parameter form Hypercore. This has been discussed several times (in discord and in referenced issues) so I decided to create this PR to test the idea out.

• All tests pass
• No new functionality is added so this does not add new tests
• documentation: All this adds is a supertrait, which is documented

Context

This would close #109 and supersede #113

Semver Changes

Breaks comparability

Performance

compilation

The build of the hypercore crate itself was slightly faster ~3 second vs ~4 seconds. Which is expected since this removes monomorphization.

Dependent crates would also probably have faster compilation times, but I have not tested that.

benchmarks

It looks like there was no significant change in performance.
I ran cargo bench -F cache on master then on this branch. These were the results:

     Running benches/disk.rs (target/release/deps/disk-3fb308ce5fa1aefb)
slow_call/create_disk   time:   [271.60 µs 279.19 µs 286.45 µs]
                        change: [-16.462% -14.634% -12.494%] (p = 0.00 < 0.05)
                        Performance has improved.

slow_call/write disk    time:   [152.61 µs 155.05 µs 157.58 µs]
                        change: [-0.3795% +1.4127% +3.1796%] (p = 0.13 > 0.05)
                        No change in performance detected.

slow_call/read disk     time:   [27.398 µs 28.185 µs 28.979 µs]
                        change: [-2.8723% -0.0003% +3.1770%] (p = 1.00 > 0.05)
                        No change in performance detected.

slow_call/clear disk    time:   [101.25 ns 116.55 ns 133.87 ns]
                        change: [-35.021% +4.7522% +60.371%] (p = 0.85 > 0.05)
                        No change in performance detected.
Found 11 outliers among 100 measurements (11.00%)
  4 (4.00%) high mild
  7 (7.00%) high severe

     Running benches/memory.rs (target/release/deps/memory-fe94faadab210ef0)
create memory           time:   [28.283 µs 28.327 µs 28.376 µs]
                        change: [-11.992% -11.611% -11.244%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 19 outliers among 100 measurements (19.00%)
  3 (3.00%) low mild
  8 (8.00%) high mild
  8 (8.00%) high severe

write memory            time:   [27.698 µs 27.734 µs 27.773 µs]
                        change: [-6.0768% -5.8230% -5.5992%] (p = 0.00 < 0.05)
                        Performance has improved.
Found 3 outliers among 100 measurements (3.00%)
  1 (1.00%) high mild
  2 (2.00%) high severe

read memory             time:   [4.3834 µs 4.4517 µs 4.5057 µs]
                        change: [-4.7051% -1.3563% +2.0805%] (p = 0.44 > 0.05)
                        No change in performance detected.

clear memory            time:   [39.149 ns 39.615 ns 40.137 ns]
                        change: [-12.839% +1.4443% +19.445%] (p = 0.86 > 0.05)
                        No change in performance detected.
Found 12 outliers among 100 measurements (12.00%)
  4 (4.00%) high mild
  8 (8.00%) high severe

[cowlicks]

cc @Frando @ttiurani @yoshuawuyts @bltavares please let me know what y'all think about this! Thanks

[ttiurani]

Thanks for this!

Given hypercore and hypercore-protocol-rs are very closely connected, in order to really test this, both need to work together.

Can you create a corresponding Draft PR for hypercore-protocol-rs so that cargo test --features js_interop_tests and cargo bench there can be run and tested?