Grid Collision System Robustness Issues

[randomPoison]

• [x] Automatically adjust grid size based on size of objects in grid. This should happen as part of the BVH update to reduce redundant processing.
• [ ] Intelligently subdivide work regions. Currently the system only creates half-spaces along the primary axes, so if the region of space that has collidable volumes is not centered around the origin it will not be properly subdivided. The collision system should track the bounds of the area in space that has collidable volumes in it and the grid collision system should split along the middle of that region.