MBS-6022, Add .gif/.png support to add cover art uploading.
MBS-4376, server side changes.
MBS-6022, Add .gif/.png support to add cover art uploading.
Merge branch 'mbs-4376-server-changes' into mbs-6022-part2

* mbs-4376-server-changes:
  MBS-4376, server side changes.
MBS-6022, Change cover art upload iframe to request upload signature from a /ws/js endpoint before submit.
MBS-6022, remove side effects from validate_cover_art_file and rename it to get_image_mime_type.

Also add a sub restore to Edit::Release::AddCoverArt to correctly
display older versions of this edit.
MBS-6022, use edit.display_data.artwork.comment where it should have been edit.display_data.artwork.suffix.
Merge branch 'beta' into mbs-6022-part2

* beta: (200 commits)
  Use new page version in the wikidocs edit page form (MBS-6226)
  Addressing comment on pull request 280
  MBS-6501: utf8-encode username and password for md5'ing
  MBS-5487: update text to correct specificity
  Fix Controller::Edit::Open test, erroneous </li>
  MBS-6519: Fix column span on /recording pages
  Remove tests that remember me tokens are one-use
  Fix remember me token tests
  MBS-3663: fix up no-vote email test
  mbs-6212: removing pointless main header
  mbs-6212: bringing titles back (oops :) )
  mbs-6212: making change-pass not profile-like when logged out
  MBS-6504: add test
  MBS-6504: don't use the freshly-bcrypted password to create the ha1
  mbs-6499: modify / remove tests
  Switch to a MOVED file so people darn well know they don't have the right checkout.
  mbs-6499: removing more nag stuff and no nag flag
  mbs-6212: remove unneeded extra whitespace
  mbs-6212: revert remaining code for donation-on-profile
  mbs-6499: Removing nag stuff from ws/1
  ...

Conflicts:
	root/edit/details/add_cover_art.tt
MBS-6022, rename %args for post_fields call to %s3_policy.
Merge branch 'beta' into mbs-6022-part2

* beta: (55 commits)
  Use correct schema in CREATE EXTENSION pgtap call.
  Fix crash in release editor seeding
  Run GenerateSQL
  MBS-6454: <Enter> should submit edit relationship type page
  MBS-6498: Support unformatting submillisecond durations
  MBS-6275: Attempt to correlate changed release events in edits
  MBS-6369: Add area bubbles to artist/label forms
  Fix MusicBrainz::Server reference to get_collator
  MBS-6548: Partial merge of MBS-5487 for ModBot
  MBS-5958, do not include deleted tracks in ReleaseDisc.sorted_tracks.
  mbs-6414: remove cruft from wikidata URLs
  MBS_6538, musicbrainz-server handles the /track/:mbid to /recording/:mbid or /release/:mbid redirect, so remove it here.
  mbs-6413: add text if there are no releases for an area
  MBS-6537, searching for an MBID should also find tracks.
  MBS-6417, output disc position in media entries in /ws/2/ json.
  MBS-6536: test
  MBS-6426: Do not destroy release events when editing other release information
  MBS-6426: Accept Edit::Release::Edit edits that delete release events
  MBS-6536: alias DateTime to DT since we also import DateTime from MB::S::Types in EditorOAuthToken
  Revert "MBS-6426: Accept Edit::Release::Edit edits that delete release events"
  ...

Conflicts:
	root/release/cover_art_uploader.tt
Merge branch 'mbs-6022-part2' into beta

* mbs-6022-part2:
  MBS-6022, rename %args for post_fields call to %s3_policy.
  MBS-6022, use edit.display_data.artwork.comment where it should have been edit.display_data.artwork.suffix.
  MBS-6022, remove side effects from validate_cover_art_file and rename it to get_image_mime_type.
  MBS-6022, Change cover art upload iframe to request upload signature from a /ws/js endpoint before submit.
  MBS-6022, Add .gif/.png support to add cover art uploading.
  MBS-4376, server side changes.
  MBS-6022, Add .gif/.png support to add cover art uploading.