Enforce minimum permission in the rest methods

[andersfylling]

There is no permission check locally before the request is sent, and this is both a waste of time and rate limits.

Add minimum permissions required to sent a given request in the method itself. Params should be added ontop as needed, as these can be dynamic.

Suggestions:

1. An exported function that links the function pointer to a set of permissions. This way disgord users can also check what base permissions a REST method requires.
2. Specify the permissions directly in the method itself. Giving outsiders no information unless the method is called.