Re: repo-config needs a prefix.

While I do agree that it would be better to give nicer message
when running "git-fetch" in bogus places, I do not know if your
patch is the right fix.  Especially, I am not sure if this
change meshes well with this fix a few months ago.

commit 4d599e6bb46d6ef3276425af34922fdbf3aac473
Author: Linus Torvalds [off-list ref]
Date:   Thu May 25 08:22:42 2006 -0700

    bogus "fatal: Not a git repository"
    
    I was just testing that "git ls-remote" change by Junio, and when you're
    not in a git repository, it gives this totally bogus warning. The _target_
    obviously has to be a git repository, but there's no reason why you'd have
    to be in a local git repo when doing an ls-remote.