[PATCH 0/3] credential-cache: give daemon a predictable cwd

The credential-cache--daemon may live forever in whatever directory it
happened to be spawned in (in practice, probably the root of some git
repo's work tree). This can prevent umount from unmounting a filesystem
that contains that directory, even though credential-cache doesn't care
one way or the other.

Jon Griffiths sent a patch to me and to the list, but it seems that vger
blocks all mail from yahoo, including him. Eep. So he and I had some
off-list back-and-forth, and ended up at this series, which I agreed to
pass along.

I've made a few minor tweaks from the last version he sent me. Hopefully
nothing he disagrees with, but of course he has no means to complain to
the list if so. :)

  [1/3]: credential-cache--daemon: refactor check_socket_directory
  [2/3]: credential-cache--daemon: disallow relative socket path
  [3/3]: credential-cache--daemon: change to the socket dir on startup

-Peff