Although 'git help' actually doesn't need to be run inside a git
repository and uses no repository-specific information, it looks for a git
directory. Searching for a git directory can be annoying in auto-mount
environments. With this commit, 'git help' no longer searches for a
repository when run without any options.
7c3baa9 originally modified 'git help -a' to not require a repository.
This applies the same fix for 'git help'.
Signed-off-by: David Aguilar <davvid@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>