Fixed some bugs!

I received a bunch of feedback about usability so I made a couple quick fixes to address them. Namely:

• FIX - Can't move the characters off-screen anymore
• FIX - Pathfinder won't fidget around and land on places behind an obstacle while player is dragging a character to a new destination
• CHANGE - Only need to tap once to transition to next screen. Transition triggers when  character moves over the button.