Added a controller for tutorials - it looks in the
/tutorials/tutorials_data.txt file and parses the data to create
a .html file for each .md file posted there, then creates an
index page. 
Couldn't figure out how to save the data from the controller
correctly (it only showed on some subpages) so the sidebar
parses the data again.
The tutorials are now shown embedded in the page with
disqus comments enabled. The syntax is highlighted using
Blogofiles syntax highlighter. To do this, we export data from
the notebook to markdown format, then parse it to add the
needed $$code(lang=python) tags.