KinematicCollision should be renamed to CharacterCollision

[MeBadDev]

Now KinematicBody is renamed to CharacterBody, we should probably rename KinematicCollision to CharacterCollision to avoid confuses and it will probably make things easier, does that make any sense?

[outobugi]

Afaik the move_and_collide, which returns that object, is now a method of PhysicsBody, so it makes sense to have 'Kinematic' in the name.