Document cbc with markdown/ronn for manpages

ronn is a tool to generate manpages from markdown. The advantage in
placing our documentation are markdown is that it's also easily readable
from github as well as Doxygen.

This version documents the new cbc very extensively.

Change-Id: I26dabb8d4f944caa1300c9c4ede9be11594eddc6
Reviewed-on: http://review.couchbase.org/38688
Reviewed-by: Brett Lawson <brett19@gmail.com>
Tested-by: Mark Nunberg <mnunberg@haskalah.org>