Incorporate Pol's AWS provisioning code

[pmcharrison]

@polvanrijn will share his code from the cap package that provisions servers on AWS that can then be used by dallinger docker-ssh.

As a first step, probably just making a new command:

dallinger docker-ssh provision ec2

In the future we could consider doing that automatically as part of the deploy command.

[polvanrijn]

Here's the relevant two files containing the code: provision-code.zip

I think the adaptation to Dallinger is fairly straightforward. I think a good documentation for future users would also be very useful. For example on how to setup Route 53 and EC2.

[pmcharrison]

Thanks Pol!