Add Docker support

[pataquets]

Docker image build file.
How to test:

$ docker build -t rockmongo .
$ docker run -d --name rockmongo -p 80:80 rockmongo
$ docker run -d --name mongodb-test-server --net=container:rockmongo mongod --nojournal --noprealoc

Also, I encourage project maintainers to create an official image on Docker Hub. I'll gladly help to push this formward. The best option would be to create an automated build, linked to Github source repo which will trigger new image builds on each commit.
As soon as it is OK, we can figure out a way to make it work via Docker links, so no there would be no need to share container network stack or modify config.php. This would be easily achieved via an environment variables aware config.php version file.

[pataquets]

You can also check and use my automated Docker image build, based on my Github forked repo:
https://hub.docker.com/r/pataquets/rockmongo/

To tinker with config.php, the easiest is to mount an external config.php file from the host file system by adding to the run command line:
-v /path/to/local/config.php:/var/www/html/config,php

[pataquets]

Bump.

[pataquets]

Linking issues #96 & #107