Fixed Quadtree indentation that was causing insert/search issues
Added debris demo to highlight performance increase from Quadtree
Fixed README example #12
Updated example to work with new collision architecture
Optimised canvas rendering by caching particle colors and batch drawing them
Batching for particle drawing in canvas renderer using `drawImage`
Reverted to arc drawing since batch `drawImage` didn't give desired performance improvements
Demo tweaks and canvas renderer optimisations #10