v0.5.8

Discogs is asked after MusicBrainz and Wikipedia, and it reaches records
neither of them has. It copies the back of the sleeve rather than modelling
it, so a Sonny Stitt date that MusicBrainz has nothing at all on comes back
with a producer on every track and a writer on every side.

• Discogs is the third place the app looks for composers and producers. It
  is only ever asked about fields the first two left blank.
• A 1960s "Supervised By" line is read as the producer credit it actually
  was, which is how names like Esmond Edwards reach the albums they made.
  Executive, reissue and assistant producer credits are deliberately
  ignored, so nobody is credited with a session they were not at.
• Writing teams are split into the people in them. A sleeve that says
  "Rodgers & Hart" is filed as Richard Rodgers and Lorenz Hart, so each of
  them is searchable and each gets a page of their own.
• A lone surname gets its first name back when exactly one person on the
  record carries it.
• New M4A to MP3 converter under Settings, Tools, Convert audio formats.
  Each M4A is replaced by an MP3 in the same folder with its tags intact,
  and the original goes to the Recycle Bin once the new file is confirmed
  good. Anything that fails to convert keeps its original untouched.
• That converter exists because an M4A has nowhere to store a producer
  credit, so credits found for one used to stay in the app and never reach
  the file.
• A placeholder credit like "Unknown" still shows as a capsule on the album
  page but is no longer clickable, since there is no page behind it.