Support for git-annex

Hi,

beets is cool stuff, I just want to share my point-of-view:

i have stored my music in a git-annex [1] library. ( but they are also exported via smb ) (i do same for my videos, iso's, some backups... )

Now, the standard beets "rename" ( or "fix track names" ) seems not work in this scenario properly, so in git-annex a "renaming" is more a "git mv A B " than a "mv A B"

For the moment i work with "git-annex unlock" and "git-annex lock" afterwards.

...or maybe there is a more clever way to do so ?
.ka7
1] https://git-annex.branchable.com/walkthrough/

Start with beets' standard "rename" or "fix track names" entry point and reproduce the behavior in a git-annex library exported via SMB. Compare the current filesystem rename with the issue's proposed git-annex workflow using "git mv" rather than manual "git-annex unlock" and "git-annex lock". Done means track-name fixes work correctly for git-annex-managed music.

Written by the indexing model from the issue text.