artist_request now tagtyped to artist

I understand the logic behind making artist request an artist tag, but practically, this means that posts tagged "artist_request" will now not show up in a artisttagcount:0 search. I was going to change it back but figured it might be worth some discussion first.

Artist request is not an artist, but a lack of one, just as source request is not a copyright and character request is not a character.

Absolutely should not be an artist tagtype. That completely eliminates the functionality you described.

Man, somebody went ahead and made character_request a character, and source_request a copyright. Changing them all back now.

Just weighing in to say, yes, these should stay general tags. Thanks for fixing.