Fix a bug where, if a ReST class attribute was set on a transition, it would blow away the class="step" that we set.
When a ReST class is set on a table, translate this to a css class on the html table.
Fix bug where classes set on a paragraph were dropped.
Turn ReST containers into html divs.
Add the ability to use ReST :name: to set an id on divs and tables, and fix handling of empty css class.
Merge pull request #19 from cjw296/classes

A bit more handling of classes and ids.