check if vibrator is available first.
added more sounds, attempted to normalize sounds.
Attractor Algorithm changed

#10 finished
force relative to distance and affected by the speed variable.
added more forces to level 3 for testing.
Update mainScreen help button
Update HelpScreen.java
Update HelpScreen.java
Update HelpScreen.java
Switch objects.
Switchable moving walls and teleporters.
Moved level end sound to the level object.
Fixed entering initials for saved high score.
Merge branch 'master' into kevin
tweaked button layout on mainscreen
Update CreditScreen.java
level tweak
Merge branch 'master' into kevin
added a switched moving wall at the end of level 1
Convert world object graphics to all be sprite sheet based
added in a basic graphic for the attractor force
animated attractor force
removing the save button #38
added sounds to the switch objects