Add method for syncing a Sprite's hitbox to it's pymunk Shape

[Cleptomania]

Previously if you updated the texture of a Sprite(and in turn, it's hitbox) or just updated the hitbox of the sprite through any means. This change does not propagate to Pymunk when using the builtin pymunk physics engine. In order to make this happen currently you need to remove and re-add the sprite to the engine, which is a costly operation.

This adds a new method to the physics engine for triggering an update of a sprite. Which generates a new Pymunk shape based on the current hitbox of the sprite, and replaces the existing shape with it. This should be much less costly then fully removing/re-adding the Sprite.

Currently this is not automatically triggered so it's still up to the user on calling this function to update the sprite, open to ideas on how this can be triggered automatically when the Sprite's hitbox is synced to the texture for example.