Added grade struct
Added test for grades parser
Grade parsing implemented, requires further testing
Added assignments page with lots of data to TestData folder
Renamed test data file
Tests failing with no assignments
Tests passing for the cases with no assignments
Added empty class and storyboard for grades table view
Added grades cell subclass
Added getGrades method to datastore
Now also parsing grades in getAssignments function. Needs more betterness
Fixed bugs introduced by swift changes
Fixed swift bugz
Added notification listener
Added listener for error notification and alert message