The mental model for clone is that the branch is "checked
out" (and it even says this in Documentation/git-clone.txt:
"...creates and checks out an initial branch"). Therefore it
is reasonable for users to expect that any post-checkout
hook would be run.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>