Finished pathfinder

- Added loaded boolean to AIMesh
- Removed old collision map from the handler, now only handles
intersection of objects
- made mesh protected, added a get function to the pointer of it
- Added oncollision for minion with example functionality
- Added A-Star pathfinding code
- Added distanceWith squared function (faster than regular), will
replace distance checks later on
- Added new Vector2 operators (divisions, multiplications with constants
and vectors)
- Why did I upload debug prints
- Fixed small codestyle error
- CollisionHandler now inherits the pathfinder.
- Optimised Object::collide. Even though nobody probably uses it. I
probably should.