Util: corrected is_type() for x = nil.
Math: fixed typos in operators.
Math: return self in normalize() and rotate().
Core: added display_size vectors.
Camera: replaced guts with vectors; corrected wacky translation.
main: added HID.Mouse.pos (updated per frame); tidy.
Scene/STUB: replaced mouse1 bind with escape-quit bind.
Camera: reworked interface; tidy.

Scene/Main:
	updated bindings and camera handling;
	added camera-centered square.