small fix to the game

To start is that when the player pick up a other powerup the player will switch powerup.

 This Switch Powerup code uses parameter string and function so when Player collects powerup it will call the function and destroy the previous object and create the new one.

The next small update is now in level 2 and level 3 because of the camera if the player accidentally fall in the beginning there will be blocks to catch the player.

the last thing is the ice Mario dash sprit was small but now it is the same size as ice Mario.