SpatialGrid: Cells are now HashSets instead of ArrayLists
ToolTraceDrawer: Null check
ToolManager: Repaint now happens immediately on tool change
ToolContextual: Fixed history being marked even when nothing happened
EditorWorld: Expanded toString() for easier debugging
EditorPanel: Added null check on camera
EditorController: Re-enabled debug stuff
Camera: Added null check on lerp-to-bbox