Add PSR-16 rate limiter

[BrianHenryIE]

As mentioned in https://github.com/nikolaposa/rate-limit/issues/45#issuecomment-810753421

There's a failing test that doesn't fail when I step through the code. I'll have to come back to it, but maybe you've suggestions for why it's happening.

[nikolaposa]

I think something is wrong with that inline CacheInterface implementation in the test itself. I don't have time to dig deeper, but try debugging inside it_silently_returns_correct_status_when_limit_is_exceeded() test.

[BrianHenryIE]

Thanks to @karneds the tests are passing and the code is updated to v3.