Regain a part of the tower price when selling a tower.
Create the trap system and add a trap (jumpPadTrap) in the main map.

Can load and manage trap points in monster path.
The JumpPadTrap has 1 chance in ten to be executed.
Add DeathPoint type used to destroy a monster without loosing life.
Add horrible bullet image and jumpPad image.
Manage the change of the MoveManager in a trap.