Creating a docker image for nominatim

Thanks for the cool installer script. We've created a Dockerfile [1] to automate creation of a docker image based on ubuntu 14.04 with nominatim installed. The result is an standalone docker image that can be started with docker run. By invoking "make build" and "make start" on any system that supports docker [1], you will be able to access nominatim at localhost:8080

[1] https://www.docker.com/