Update contribution section

[LivInTheLookingGlass]

It should include some notes on style fixing. These should basically say that if you submit style fixes, such as those pointed out by codeclimate, then they are considered licensed under this repository unless specifically requested otherwise. It should also point out that these changes ale fast-tracked, and that they should not be mixed with other PRs if possible.

I know that I violate that last one occasionally, but I will make an effort not to do so in the future.