Move policies into a git repo

[m]

better revision control, better forkability. better diffability

downside: a bit higher barrier of entry to edit. maybe this is good for things that need to be publicized and voted on, though?

We probably need to do a render step to publish policy somewhere with whatever we end up with. maybe in the same vein as the bylaws?

Maybe mirror them to mediawiki? Or have them in a specific place on our website? Need to be able to point to a list of policy, maybe sorted by most recent (most recent being a proxy for most representative of the current population of the space)