Kick off client additions with Java

Contains the java client docs as a first class citizen (http://docs.basho.com/java/latest/).
This PR also has many changes that allow for the integration of those java docs, as well as the addition of other projects in the future. The initial design was very riak-centric, this recalibrates the orbit to be the `version.yml` file which defines active document projects (I'm considering possibly renaming the file to a more descriptive `projects.yml`).