Staging for parking_lot 0.9.0, _core 0.6.0 and lock_api 0.3.1 releases

[dekellum]

This includes all necessary version changes and overhauls the CHANGELOG to show more recent releases for all three crates (parking_lot, parking_lot_core, lock_api). Before releasing, the top (TBD) should be replaced with the current date and tags for all crates added. I also request that you add the following tags to this repo retroactively:

git tag core-0.5.0 3259fd72e0d76e9c9a6f31ff41a996648fe9ccfa
git tag lock_api-0.1.5 2653619a613bc12dd6ab486f789d98956b65cdf0
git tag lock_api-0.2.0 3259fd72e0d76e9c9a6f31ff41a996648fe9ccfa
git tag lock_api-0.3.0 ace8280969b6362c3f3753506d90122c358de580

Fixes #158

[dekellum]

The rendered CHANGELOG for preview.

[dekellum]

The appveryor CI failure appears unrelated?

error occurred: Failed to find tool. Is `gcc.exe` installed? (see https://github.com/alexcrichton/cc-rs#compile-time-requirements for help)

[dekellum]

master branch commit da16c2c is a fix to lock_api, so bumped version to 0.3.1, merged it here and updated CHANGELOG for that.

[dekellum]

@Amanieu do you also want to yank lock_api 0.3.0, in light of the findings of da16c2c?

[Amanieu]

@Amanieu do you also want to yank lock_api 0.3.0, in light of the findings of da16c2c?

Good point, I just yanked it.

[Amanieu]

Thanks a lot for the help! I have published new crate versions and added new tags.

[matklad]

I am a little worried by

Rust 1.31 may continue to work for normal use of these releases.

rand bumping msrv is definitely not a parking_lot fault, but still, the end result is unfortunate. Can I rely on parking_lot working with 1.31.0 or not? If I can, I'd be happy to send a PR that updates readme and adds a compile-only CI job for 1.31.0. I am also not against bumping msrv of reversed deps to 1.32.0, it's just unclear what is the current stance :)

[Amanieu]

Yes, parking_lot should work fine on 1.31. It's just that the tests don't compile because of rand (which is only a dev-dependency).

I am happy to accept a PR to clarify this in the README.