Add repo location(s) to status page

[a-m-s]

My project code spans multiple git repos, and I have multiple instances of the project in different locations, all open in multiple windows, so it can get confusing sometimes.

Please add a new header line the the status page with the absolute path location of the worktree (and .git, if different, might be nice too).

It's nothing I can't figure out from :pwd, of course, but would be nice to have all the same.