Some of these might not occur in the wild, but we theoretically support
them at least, and making sure they work might catch other issues we
didn't think of yet.
I left the "THOMAS" part in for now, but this seems more like a debug
message than a user facing message to me—but it was also obviously
something @thomasvs left in for himself, so maybe the whole if clause
has no reason to still be there and should just get removed.
Some of this seems to be debug code which has been left in, some of it
seems to just be old code that was commented out and never put back in
and probably just forgotten about. Either way, we use git for a reason,
so there's no need for these code snippets to stick around. The code
history can be inspected and old code retrieved that way.
Make MusicBrainz consistently written as "MusicBrainz" and not
"musicbrainz" or "Musicbrainz".
Doesn't change instances that refer to the Python module or similar.
