Update workstudy.rst

Basic text edits.
Allow nulls and blanks where no sane default value exists
Merge branch 'master' into develop
Add (but not remove) models, fields, and data for course sections
South sorcery: fall back to querying the `through` table directly when M2Ms start throwing KeyErrors
Remove obsolete fields
Remove some `null=True` hacks
Merge branch 'jnm-course-section-migration' into course_sections

Conflicts:
	ecwsp/schedule/models.py