dockerize

This adds Docker support.  There is a `Dockerfile` that is intended to be used in an automated build on the Docker Hub.

This also adds the ability to bring up an entire stack locally (you will need docker installed):

From the cloned directory:

`docker build -t snipt/snipt .`

Then

`.docker/start.sh all`

That will start a complete stack (postgres, elasticsearch, app and proxy).  You can view the app on port 8000.

`.docker/destroy.sh all`

This removes the entire stack.