Should `collide-with` be deprecated in favour of `collide-with!`

[simon-brooke]

The function collide-with modifies its third argument, an instance of CollisionResults, by potentially adding a new CollisionResult object. It's conventional in Clojure to mark functions which are not pure functions with an exclamation mark suffix.

I propose:

1. create a new function collide-with! with the same code as the existing collide-with;
2. alter collide-with to call collide-with!;
3. deprecate collide-with in favour of collide-with!.

Let me know whether a pull request to this effect would be acceptable.

[ertugrulcetin]

Sure, if you create a PR, I'd happy to merge it

[ertugrulcetin]

@simon-brooke I sent you an access permission to this repo.