Chapter Prose

First draft of the chapter prose, in rst form for now. I'm requesting PR to have someone look at the prose. I've also included an svg diagram, but you'll have to pull the repository to see it. I don't think it's viewable within github...

If you want to pull this, this is the 'chapter' branch from https://github.com/malini/500lines
This wording feels a bit awkward to me; maybe something like:

By separating concerns into their own processes, we were able to build the fundamentals of a distributed continuous integration system. With processes communicating with each other through socket requests, we are able to distribute this system across multiple machines, helping to make our system more reliable and scalable.