Adds new and changeable bar signs to the game.

17 new bar signs were added including the empty one that is only used as a placeholder
Signs:   ![] (http://i.imgur.com/DRd8P2A.png)
A bar sign is randomly assigned at round start so even if no ever bothers to change the sign, it won't always be the same round to round.
Bar signs can be changed to any of the 17 choices (Not including the empty sign) by anyone with bar access or the AI
All sprites were used with the permission of their owners.  
Code was originally done by N3X15 with alterations by Mrperson, menshin, ikarrus, and myself.

Please tell me if i messed something up, this was a lot more complicated and I had to have a lot of help.
This is how it's done on /vg/.  The bay code uses inputs which is apparently worse.