[PATCH 0 of 1 stable] hg.clone() fix/question

[Augie Fackler]

This patch fixes hg.clone() when it is passed a repo instead of a
source path. This broke a month ago and nobody seems to have
noticed. I only noticed because this pattern of passing a repo object
was used in some internal tests on Google Code. Perhaps rather than
fix this it makes more sense to stop supporting passing a repo here
and only accept URLs? If that's the general feeling, I'll resend to
clean up the cruft.