Makefile

For now, git-remote-mediawiki is only a remote-helper. This patch adds a new
toolset script in which we will be able to build new tools for
git-remote-mediawiki.

This toolset uses a subcommand-mechanism to launch the proper action. For now
only the 'help' subcommand is implemented. It also provides some generic code
for the verbose and help command line options.

Signed-off-by: Benoit Person <benoit.person@ensimag.fr>
Signed-off-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>