zsh completion todo

[ThomasWaldmann]

Likely incomplete todo list for the borg2 zsh completions (please do your own practical experiments):

• borg1 had REPO::ARCHIVE as "url" (e.g. ssh://u@h/path::archivename), borg2 now has -r REPO ARCHIVE. The giving REPO on the commandline is optional and can be replaced by setting the BORG_REPO env var. Guess the old archive completion does not work anymore.
• check all __functions in the completion code
• _borg_remote_repositories we now also have sftp: and rclone: remote repos
• _borg_archive: hints, integrity, index files are not there anymore, but config/readme is.
• _borg_format_keys needs to get split into 2 function, one for borg list archive and one for borg repo-list.

Code:

• https://github.com/borgbackup/borg/blob/master/scripts/shell_completions/zsh/_borg

Docs:

• https://borgbackup.readthedocs.io/en/2.0.0b13/usage/general.html
• https://borgbackup.readthedocs.io/en/2.0.0b13/changes.html