Changed size and position of pause/play buttons and changed value of negative points powerup
Merge branch 'master' into helpScreenLayout
Adjusted pause/play buttons to final position
Added PowerUps help screen label
Added placeholders for image assets on help screen
Added Good and Bad PowerUps placeholders
Added persistence on high score and square count. Not able to test sound.
Fixed First Session Bug
Pre Merge Commit - Fixed minor issues
Merge branch 'master' into UserDefaults
Merge pull request #16 from ranleung/UserDefaults

User defaults
Added preliminary game center support
Merge branch 'master' into gameCenter
Added sound button functionality
Added GameCenter Button and Image
Merge pull request #17 from ranleung/GameCenterButton

Added GameCenter Button and Image
Changed and moved rules on help screen
Merge branch 'master' into helpScreenLayout
Small merge conflict fixed
Merge pull request #18 from ranleung/helpScreenLayout

Help screen layout