Added school_type and grade property to Student model.
Added school_type and grade property to Student model.

A GAE Task will be provided to update the existing entities in a later commit.

Reviewed by: Lennard de Rijk

MatthewWilkes/mw4068-packaging,MatthewWilkes/mw4068-packaging,MatthewWilkes/mw4068-packaging,MatthewWilkes/mw4068-packaging