Fix areas, places in the relationship editor (MBS-6851, MBS-6883)

The "type" properties returned from /ws/js conflict with the "type" set by
MB.entity (e.g. type=1 vs. type="area"). This renames type to typeID in the
webservice (AFAICT, it isn't used anywhere).

This also fills in MB.entity.Area and other missing references needed for
things to work.
Fix reference to typeID in the release editor's information tab
Generate allowedRelations automatically
Merge remote-tracking branch 'bitmap/mbs-6883' into beta

Conflicts:
	lib/MusicBrainz/Server/WebService/JSONSerializer.pm