Added the new upgrade path (dual and single big shot)

Alot of little tweaks.
Changed bomb to not destroy bosses(wrong tag used)
Bomb gui now display # of bombs left to use and when none left, button
disappears.
# of bombs is hard coded for now, can be updated to be used with
facebook challenge
Also added shields and changing color of the ship
other code in Done_Gamecontroller changed in how upgrades are done