added a process-role template to preserve @role attributes as html class values; also added an include-toc parameter (default=true) to include the TOC after the titlepage
tweaked handling of process-role template
Merge pull request #13 from oreillymedia/sarah

Added a process-role template (to preserve @role attributes as class values), and added an include-toc parameter
Merge branch 'master' of github.com:oreillymedia/docbook2htmlbook into informalfigure
Yes, still want to include <img> in standard figs :)