prep repo to auto-generate pretty documentation with yardoc

Before this commit: "Use the source, Luke!" is the only way
for somebody to read what's going on within the repo.

After this commit: The local repo has gems that enable to
render pretty HTML docs based on tags and comments within our code
based on http://yardoc.org/ native comments and tags, similar to
http://rubydoc.info/

Signed-off-by: Paul Morgan <jumanjiman@gmail.com>