Merge implementation with crossbeam-queue

[notgull]

From a brief glance at both crates, it seems to me that there is very little noticeable difference between the algorithm used in concurrent-queue and the one used in crossbeam-queue. It would be nice to just re-implement concurrent-queue in terms of crossbeam-queue if there are no/little significant differences between the two implementations, as it would deduplicate code in the Rust ecosystem.

[taiki-e]

IIRC, the main difference is the presence of code for the single-capacity cases (see also crossbeam-rs/crossbeam#199 (comment)) and disconnect(close) support.

[taiki-e]

I think there may also be a few optimizations that are present in crossbeam but not in concurrent-queue, such as crossbeam-rs/crossbeam#1057.