[libc++][compare] Implement three_way_comparable[_with] concepts

[libc++][compare] Implement three_way_comparable[_with] concepts

Implementation of `three_way_comparable` and `three_way_comparable_with` concepts from <compare> header.

Please note that I have temporarily removed `<compare>` header from `<utility>` due to cyclic dependency that prevents using `<concepts>` header in `<compare>` one.

I tried to quickly resolve those issues including applying suggestions from @cjdb and dive deeper by myself but the problem seems more complicated that we thought initially.

I am in progress to prepare the patch with resolving this cyclic dependency between headers but for now I decided to put all that I have to the review to unblock people that depend on that functionality. At first glance the patch with resolving cyclic dependency is not so small (unless I find the way to make it smaller and cleaner) so I don't want to mix everything to one review.

Reviewed By: ldionne, cjdb, #libc, Quuxplusone

Differential Revision: https://reviews.llvm.org/D103478