AWS setup instructions for novices

[axch]

Goal: A completely novice user can rent 32 cores by the hour to play with the probcomp stack.

Approach: Write a document that says

• Follow https://aws.amazon.com/getting-started/tutorials/launch-a-virtual-machine/, but use our AMI foo (and maybe a bigger instance type, like c3.8xlarge, to actually compute)
• At the end, make an ssh tunnel and point your browser to localhost:whatever
• Don't forget to download any notebooks and .bdb files you want to keep before you terminate the instance

Include it with the Docker document appropriately.