Pull Request 20 Rewrite

@tboyko has provided a pull request ( https://github.com/dignoe/whenever-elasticbeanstalk/pull/20 ) which resolves some issues however was incomplete.

This pull request needed to deal with AWS inadequate identification of the path to the support/containerfiles in the /opt/elasticbeanstalk/ path. I have raised this with AWS Support Forum ( https://forums.aws.amazon.com/thread.jspa?messageID=581694&#581694 ) but have yet to see any activity.

This *should* work with environments using *either* /support or /containerfiles.