Aaron Wells authored Sep 02, 2016 and Robert Lyon committed Nov 03, 2016

This patch adds a Dwoo precompiler on styleguide.php.
It locates all the code samples (as delimited by markup
"```" delimiters), and makes two copies of each one.
One is passed on to Dwoo to be compiled and rendered,
and the other is surrounded with ```{literal}{/literal}```
so that the Dwoo tags in it will remain uncompiled,
and the markdown renderer can render it into code.

We were previously doing this on the JS side, but then
the rendered examples couldn't properly render
Dwoo tags in the examples.

behatnotneeded - guide only no core functionality

Change-Id: Ic55a972437d1c2c8f88169d501a48735b8fd303b