One use case on design
Move Cocos - it is a detail
First passing specs on buckets - movement
Display the buckets
Use case 1 complete

The 'buckets' now move.

Note that there is logic in BombingLayer.  We'll come back to that.
Convert to ARC
Add Bomber to design
WIP: Use Case #2

- Start moving the bomber back and forth.  Next to wire it up and show
  it on screen.
Update design.  Removed whitespace