Clarify the difference between nbAlbums & albums().size()

As described and asserted a few lines above, the candidate album
AlbumArtist can't be nullptr

This is now handled by a specific task table in DB

We use this for entities ID which are always 64bits integers

All unit tests used to start the notifier, while it's only needed for a
single set of tests

We never run the parser from unit tests

Until VLC handles those without lua, we can't do much with those files

Soomin Lee authored Aug 04, 2017 and Hugo Beauzée-Luyssen committed Jan 23, 2018

Signed-off-by: Hugo Beauzée-Luyssen <hugo@beauzee.fr>

As opposed to the previous strategy, which was requiring every artist to
have at least an album

This doesn't contain the migration code as there is more changes to come
into the Artist table, and those change would basically roll back most
of this commit associated migration code

So that we don't break the logic for released versions

In order not to confuse them with media we failed to parse

6 to 7 migration will remove all albums & artists anyway, so there's now
no need to update their values during 5 -> 6.
The test is removed as regardless of the migration, it would now yeild
success due to the inversion of the condition when fetching present
entities (is_present = 1 became is_present != 0)

Relying on foreign keys might not work of something is poorly
tagged/analyzed.