Update the commit documentation with better example
Add Tianon to contrib/ maintainers

He's awesome and always contributing to this area.
Prevent panic upon error pulling registry
Merge pull request #1897 from dotcloud/update_doc

Update the commit documentation with better example
Merge pull request #1898 from dotcloud/smallfix_registry

Prevent panic upon error pulling registry
Merge pull request #1893 from dotcloud/add-tianon-maintainer

Add Tianon to contrib/ maintainers