Fix inaccurate versionchanged tag for compressobj(): most parameter were there, just got kwarg support.

Skip tests for 24-bit wave file on big-endian platforms.

documentation.

Suggested by Skip Montanaro on docs@.

wave.

This does not fix #19227, but should stop the Gentoo buildbot from hanging.

emulation has changed from 0-based indexing to 1-based like gnu readline.
Original patch by Ronald Oussoren.