Add data for the 2012-13 summer sessions
Pass the year and semester to addCourse
Integrate the actual data for 2013-14 semester 2, rather than the interim data (again)
Do some extra checking inside of getCourse
We actually *do* care about the zeroth column in the CSV files.

Courses can be 'cancelled'.
Removed a comment.
Add support for summer sessions
… that OrderedDict module will work better if I import it, won't it.
Remove the code for parsing the old (non-yaml) student files
Add the isinstance check to Student