Add myself as an author 7e09c633

One of my patches was incorporated into Docker, and at that time I didn't know that I was supposed to add myself into this list of contributors.

Commit ID: 7e09c6332d

And a few other patches are already in the pipeline.

AUTHORS

@@ -69,6 +69,7 @@ Gabriel Monroy <gabriel@opdemand.com>
 Gareth Rushgrove <gareth@morethanseven.net>
 Greg Thornton <xdissent@me.com>
 Guillaume J. Charmes <guillaume.charmes@dotcloud.com>
+Gurjeet Singh <gurjeet@singh.im>
 Guruprasad <lgp171188@gmail.com>
 Harley Laue <losinggeneration@gmail.com>
 Hector Castro <hectcastro@gmail.com>