The config command is no longer needed.
Use CAA data when embedding images into files

This includes both the image type (for vorbis, id3 and asf files) as
well as the comments (as description for vorbis, id3 and asf files).

Additionally, converts the `images` attribute of
picard.metadata.Metadata to a list of dicts instead of tuples for easier
access.
Add support for Opus files (needs dev version of Mutagen)

http://tickets.musicbrainz.org/browse/PICARD-289
Merge branch 'master' of github.com:musicbrainz/picard
Fix coverart tests
Cover: Disable all cover art providers by default

Images can get quite large and not everybody might want to be surprised
by Picard eating bandwidth.
add missing `album` argument to _fill_try_list
Fix PICARD-351

_process_asin_relation was still adding URLs manually to the try_list
instead of using _try_list_append_image_url
pep8 fixes
Remove an unused import
Stop downloading coverart if an album is removed
'add new tag' writes to different field than specified (PICARD-348)
Make dropping files from newer iTunes work
Remove the jamendo cover art provider

The annotation for the jamendo label says to use the CAA and there's a
bot migrating existing cover art with only a few relationships left to
do.
Accept https URLs on drop

Fixes PICARD-378
Merge branch 'master' of github.com:musicbrainz/picard
'add new tag' writes to different field than specified (PICARD-348)
Make dropping files from newer iTunes work
Only set the ~extension tag once
Reset dirname/filename/extension tags after saving