CI Lint as a command line tool

I'm not sure if it already exist, but I didn't find nothing about this.

Description

Actually, the only way to use the CI lint is the web interface, or the API. I'm using a lot of lint tool (for ruby, puppet, etc...), and it would be really nice to have a command line tool to do the same for a .gitlab-ci.yml.

Proposal

Making this available as a command-line tool, to be able to validate a .gitlab-ci.yml from terminal. We could integrate it in some text editor (like atom, or sublime), in the future.