MBS-1413: Make profile bios support WikiFormat

http://tickets.musicbrainz.org/browse/MBS-1413

I also removed the border around the bio, because it was as repulsive as a monkey in a negligee.

Got rid of the import of user.css here, since "it's in the common CSS import, so it doesn't need to be explicitly imported on that page separately" (said Ian).

And made the whole bio code a bit less stupid by removing what seemed to me like an absolutely pointless use of a variable. If this was very important for some weird reason, shout at me!

Tested manually on sandbox, see http://reosarevok.mbsandbox.org/user/reosarevok