updated rails to 3.2.13 and added ASCIIDoctor (to replace markdown)

Signed-off-by: Darrin Mison <dmison@me.com>
using asciidoc in the HTML preview instead of markdown

Signed-off-by: Darrin Mison <dmison@me.com>
error message handler was missing (oh)

Signed-off-by: Darrin Mison <dmison@me.com>
removed markdown->docbook hackery, customised literals to use <code> and <screen> for inline monospaced and block literals respectively

Signed-off-by: Darrin Mison <dmison@me.com>