Lost work, and the perils of reset --hard

Features:
+ Added a very primitive circle collider because it is very easy and time is not on my side at the moment. Will add more advanced polygon colliders when I have time.
+ Added the ability to change background colour.
+ Tweaked the config and did a little bit of code cleanup.

Bugs:
+There is a bug in the quadrant based view partitioning code that I am using as a collision detection optimizer. I have not traced it down yet. It is disabled for now.

Story:
So, after I commited my changes tonight I pushed them to origin master (or so I thought) and proceeded to merge the changes into gh-pages where I encountered some conflicts. Being tired and wanting to go to bed I reset --hard because I thought all my nights work was in the upstream repo... Nope. I think the auth for my push before the reset silently failed. Lesson, never ever reset --hard without a backup. I should know better :(.