Fix centroid offset fix, again.
Fix initial random point bounds in distributeRandomPoints
Use offset stored in contact to explicitly resolve physics

Instead of modifying the position temporarily on the "from" object, this paves
the way to objects caching their vertices and aabb's.
Cache vertices and AABBs per frame
Add basic quadtree implementation with inserts debug drawing
Use quadtree for broad-phase collision detection
Add click intersection testing for debugging
Performance: faster Utils.pairs

The underscore.js helpers are slow compared to raw loops/indices, big surprise.
Make the ship more resistant to spinning
Replace underscore with lodash
Draw asteroids in batches for better rendering performance

* Draw polygons in batches
* Use explicit transform for groups rather than setting it globally in Display
Fewer transform calls in Geometry.minimumSeparationAxis
Minor cleanup of PolygonalBody.aabb
Faster projectionInterval calculation
Add a second tracking camera point for smoother camera motion
Minor efficiency improvement in intersection offset bounds
Merge branch 'render-performance'
No save/restore when drawing circles
Square field only
Add a missile particle on space