Optimized endpints for pulling back lots O' results

You can now exclude pseudonym info on api requests.
users_json will now preload section information when you include[]=section

Fixes CNVS-14836
Fixes CNVS-13093
Fixes CNVS-12932
Fixes CNVS-16216
Fixes CNVS-16218

Test Plan:

- Create a course with 800 users
- Create a group set; add 150 groups to set.
- Load groups page it should load way faster than before
- Make sure search isn't slow

Change-Id: Icff28b00141fb3573b9ed9493e8dc38521a368e4
Reviewed-on: https://gerrit.instructure.com/43356
Reviewed-by: Jacob Fugal <jacob@instructure.com>
Reviewed-by: Andrew Butterfield <abutterfield@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Joel Hough <joel@instructure.com>
QA-Review: Steven Shepherd <sshepherd@instructure.com>
Product-Review: Brad Horrocks <bhorrocks@instructure.com>