Ripped out levels.  Now showing topics from database on home page.
Combined poorly-named static controller and machine controller into main controller with pages named "menu" and "exercise"
Oops, missing a solution for 1R.
Fix broken link to debugger-demo-lesson
Continue button from 2 shouldn't go to demo-debugger-lesson
Bug fix: line highlighting wasn't smart about multi-line statements, semicolons, and comments