Draft: Address #68: Add syntax highlighting of examples to hemlock
We add syntax highlighting of examples to Hemlock user manual and command implementers manual.
Syntax highlighting is done using highlight js and is set in docs/texi2html.init. This supports highlighting things in @lisp and @example. This works for Lisp.
Also, we add some CSS to add a background color to examples to set off the example code from the surrounding text. This is modeled after the emacs manual.
Edited by Raymond Toy