Mikhailov/release procedure

This changes list adds grunt-shipit task to ease deployment. Added task is wrapped by custom release task. Shipit wrapper is a bit more special thing for SourceJS. Custom wrapper encloses some options, changes their representation and implements some Source-specific handlers in itself.

There is no documentation right now, unfortunately... It is going to be added asap. 
Use separate keys for envs in common options.js file.