WIP - Adding automation scripts and files for l4d2

* Adding Dockerfile to set up a container
* Adding Vagrantfile to build the image locally
* Adding l4d2server_automated script bypassing reads

DO NOT MERGE

This is an example of how to containerize one of the game servers. 

1) Create an automatable version of the l4d2server manager script. This could be the main script with an expect script instead
2) Set up a Dockerfile to prep an ubuntu box, download the script, and run the install.
3) Write a custom server.cfg over the default one
4) (not yet implemented) set up an entrypoint to start the server, wrapped behind the monitor
5) (not yet implemented) expose the ports in the container
6) Wrap the container in DNS so that it can report its hostname correctly

Honestly this is a bit of a departure from where I need to be, I think a lot of these tools are useful in a non-automated environment, but I may stick to the bare essentials and use the base commands in my setup