Specify which version of the `json` gem to use in Gemfile.lock
Use pygmentsrb to colorize bash output as well.

When we specify that a particular code block is written in Bash, it
should automatically be colorized when we generate the documentation.
Fixed a spacing typo in index page
Rewrote README to reflect  that we use nanoc instead of Jekyll now

The README now accurately tells you how to install the necessary
libraries and build the site, along with how the JSON objects and headers
in the documentation are generated.