It's very basic, only subcommands.
If this would evolve, generation of _gclient should be automized (like a separate command
or some other tool.)
Review URL: http://codereview.chromium.org/546069
git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@36521 0039d316-1c4b-4281-b951-d872f2087c98
antonm@chromium.org