Support "smart" collections
Migrated from https://bugzilla.gnome.org/show_bug.cgi?id=772465
@laurent.pointecouteau:
There are currently a lot of different ways to sort a games library: by developer, by editor, by platform, by original release date, by localized release date, etc. We should provide the user with a way to not only create collections, but automatically put games inside "smart" collections according to some criterias (e.g. "games that include music composed by Yuzo Koshiro"). Such a system should be able to rely on exhaustive metadata to work well.
*** Bug 781923 has been marked as a duplicate of this bug. ***