git-shell: accept "git foo" form This is a backport of 0a47dc110e042b5bcc63dc94c8d517e67efe9306 to 'maint' to be included in 1.5.6.2 so that older server side can accept dashless form of request when clients are updated. Signed-off-by: Junio C Hamano <gitster@pobox.com>