(1) Input - fixed touch issues + (2) fixed gate collision

(1) fixed input touch issues
-stopInput() records the moment
-Touch input functions (tap and swipe) compare activePointer start time
to stopInput time to determine if input began BEFORE the level ended
Result: smoother experience!

(2) fixed gate collision
-nested loop resused var "i", resulting in weird gate collision bugs
-simply changed inner loop to "j"!