*) First, I think that the name "Play Queue" is better.  I'm still not crazy
   about that, but for a user visible string I like it more than "Upcoming Playlist".

*) Switched the icon to use the "today" icon for now.

*) I don't see any reason to disallow removing files in the upcoming playlist;
   that seems like an unnecessary special case.

*) Don't raise the upcoming playlist when it's shown.  That wasn't concistant with
   the other "special" playlists.

*) Get rid of the "upcoming item" thing in the Playlist RMB menu and just have it
   automatically show / enqueue things into the upcoming playlist; one queueing
   system is enough, thank you.  ;-)

There are a handful of other things that need to happen here, but I presume that
those will come from Michael and I over the next little while.

svn path=/trunk/kdemultimedia/juk/; revision=339083