Merge pull request #65 from jwien001/master

Students can now only solve unsolved problems.
Merge pull request #66 from jwien001/master

Database query improvements.
Merge pull request #67 from jwien001/master

Implemented unassigned set.
CreateClass stuff

I can't test it
Merge pull request #68 from rlobo3/master

Added CreateClass pages and methods
Finished work on adding a class.