Updated Darwin filesystem name normalization documentation.
Updated Darwin filesystem name normalization documentation.

Now that APFS is out and we have a good idea of its normalization
behavior, we've decided on a strategy for handling it. Long story short:
we don't normalize for APFS, even though there may be some vestigial HFS
decompositions hanging around. It's the only sane way forward.

havoc-io/mutagen,havoc-io/mutagen