Refine and clarify some key names and hs issues

This is a refinement on @Diziet's earlier work, and tries to fix up a few key names so that they will better describe the keys in question, and generally be terser.

I've also added names for a couple of keys that didn't have names before, removed a name for a key that wasn't actually referenced anywhere, clarified various relationships, and removed "password" authentication.

@Diziet, please confirm that you're okay with this?