InProgress: Delete song(s) view model.

-Not pretty, but it will work.
-Mirroring the delete user capability, while reusing (copy/paste) code
 from the StudySongsViewModel.
-Flat out ugly, but I'm tired and I want to get it done and move on to the
 mobile stuff.

Signed-off-by: William Raiford <bill.mybiz@gmail.com>