Returned exit code 1 in case the project is not production ready.

People might like to use this app in their build script. This change allow this app to be used with CI providers like travis which rely on exit code to tell whether there was any error.
Merge branch 'master' into add_exit_code
Merge pull request #9 from agiliq/add_exit_code

Returned exit code 1 in case the project is not production ready.