Consider using more features of AWS

[jschementi]

• Now that Elastic Beanstalk supports Dockerfiles and rolling deployments, may be worth adding an option to use it rather than having Riker control the rolling deployment.
• CodeDeploy could be used for actually performing the deployment, rather than the git push mechanism RIker uses today.
• Riker could use EC2 Container Services to directly deploy a Dockerfile and let AWS manage the resources itself. (Though in preview currently)
• Riker could deploy an NPM module to Lambda.