Git's main usage pages did not show "git help" as a way to get more
information on a specific subcommand. This patch adds an info line after
the list of git commands currently printed by "git", "git help", "git
--help" and "git help --all".
Signed-off-by: Teemu Likonen <firstname.lastname@example.org>
Signed-off-by: Junio C Hamano <email@example.com>