Improve dump_course_ids test for unicode course_ids
Merge pull request #2944 from rocha/improve-dumps-course-ids-tests

Improve dump_course_ids test for unicode course_ids
Initial implementation for system_manager app
Tightened up session impl
Removed unnecessary imports
Resolved merge conflicts
Added resource URIs and documentation reference
Added test harness for API calls
Added placeholder tests and fixed a couple bugs
Added EDX_API_KEY support
Added groups
Added support for creating/retrieving users.