Rule-based preferences - format marker RFC, etc.

[Ian Clatworthy]

John Arbash Meinel wrote:

> I'm a bit curious what you are thinking with "file-ids used for magic
> files could be found more directly". Just a "Tree.get_magic_file(XXX)"
> sort of thing?

Yes. Or Tree.get_magic_fileid('rules') say. We could put '.bzrrules'
as the parameter instead of 'rules' but the '.bzr' prefix is arguably
implicit.

Ian C.