Scripting for a basic AWS deployment

This branch contains AWS CloudFormation declarations for doing a basic multi-server deployment into AWS, with auto-scaling webheads and a separate database instance.

It depends on the "awsboxen" tool I've been hacking on to perform the actual deployment, as well as awsbox obviously:

  https://github.com/rfk/awsboxen

@zaach @lloyd please take a look and see what you think.  It's highly experimental but actually seems to work quite nicely.  If you've got access to the dev moz AWS environment, you should be able to:

    awsboxen deploy --profile=MockProduction picl-mock-prod

And it will spin up a stack consisting of RDS database host, load-balancer, and auto-scaling group of frozen awsbox instances.

Unfortunately https://github.com/mozilla/awsbox/issues/43 means that the frozen awsbox images don't really work properly, they just show "sorry the server is not running".  But it's still fun to try out the whole process :-)