Refactor system.d to 100 line limit
Refactor app.d to 100 line limit
Fix system.d
Refactor entityspawns.d to 100 line limit, add vec2FromAngle converter function
Refactor playereventhandler.d to 100 line limit
Refactor collision/response/bullet.d to 100 line limit
Ensure all vector-from-angle code uses vec2FromAngle converter function
Refactor components/collider.d to 100 line limit
Refactor components/input.d to 100 line limit
Split entityfactory/entities.d to entityfactory/controllers.d
Refactor app.d to 100 line limit
Refactor entityfactory/tests.d to 100 line limit
Refactor collisionhandler to 100 line limit and simplified collision detection somewhat