Canvas sections sync calls in SpeedGrader should sync the student

Currently when performing a sync in SpeedGrader we:

* Sync the teachers user
* Sync the groups the student is a part of
* Associate the groups with the teacher

All of this is correct, however we should also **_sync the students user as well_**.

This will ensure:

* The user shows up in dev (even when we clear DBs). This will reduce confusion, testing time, and the chance that we will start to accept this as "normal broken"
* Covers a real but mild user requirement, which is that if a student has changed their name in Canvas since they last visited an LMS based assignment, this will show the updated name in SpeedGrader

## Implementation notes

* The student user id is available as Canvas extra LTI param `focused_user`
* The current user name is probably not available at this time
* We might have to go look it up using the Canvas API to make this work