Start button now rendering at correct size.
Refactored camera out of renderer. Later, we can use this to intercept clicks in ClickManager.
Removed a couple of redundant console.log's.
Start button now hittable.
Minor tweaks.
My mouse model and clickManager works with the game loop by storing click event for later processen. This idea cannot easily be united with the fact that you must request pointer lock immediately when getting a browser click event. So I took the long way around the problem by locking the mouse upfront and emulated it (inclusive rendering) myself inside of the game loop.