Add Cluster As Release 0.1 by Lukáš Lalinský

http://users.musicbrainz.org/~luks/picard-qt/plugins/addrelease.py
Upgrade to the NGS release editor

See http://wiki.musicbrainz.org/User:OliverCharles/RE_POST
Don't use cgi.escape, it's not bundled on Windows/OS X

Thanks to bitmap on #musicbrainz for reporting the issue!
Send track-level artist information (fixes VA submission)
Only set track artist if it's different from the release artist

This makes it easier to change the artist of the release and
all the tracks in the release editor (for single-artist releases).
Add new plugin extension point register_add_plugin_submenu to allow submenus in Plugins context menu
Add ability to specify the submenu for a register_*_action.
Allow submenus to be nested
Don't clobber existing submenus when the same submenu name is used by two different plugins
Add context to submenus, so they only display when required, rather than ending up with empty menus, depending on the menu's context.
Properly handle cases where a submenu is trying to be created before the parent menu yet exists.
Separate clusterlist into a separate plugin registration.
Display the port Picard is listening on at bottom right status bar (PICARD-190)
Typo-fix
Fix _clusterlist_actions.register
Restore window title to edit tag dialog; make button names translated
Fix Edit Tag window title properly
Merge remote-tracking branch 'upstream/master'
Moved plugin to correct subdir with respect to main Picard repo
Merge branch 'addrelease'