added fixes for vector class
added fixes for vector class

Luwdo/PhysicsJS,pietro909/PhysicsJS,Rawneed/PhysicsJS,rohit765/PhysicsJS,mcanthony/PhysicsJS,131/PhysicsJS,eric-seekas/PhysicsJS,haithemaraissia/PhysicsJS,pietro909/PhysicsJS,jpellerin/PhysicsJS,rohit765/PhysicsJS,Nayar/PhysicsJS,wellcaffeinated/PhysicsJS,Nayar/PhysicsJS,wellcaffeinated/PhysicsJS,haithemaraissia/PhysicsJS,Rawneed/PhysicsJS,griever989/PhysicsJS,jpellerin/PhysicsJS,griever989/PhysicsJS,Luwdo/PhysicsJS,VANITAX/PhysicsJS,mcanthony/PhysicsJS,aldeed/PhysicsJS,eric-seekas/PhysicsJS,aldeed/PhysicsJS,VANITAX/PhysicsJS