CLC-4561, CLC-4633, CLC-3812 Let Add User to Course be run standalone

https://jira.ets.berkeley.edu/jira/browse/CLC-4561

Also fix bogus "number of results" warning:
https://jira.ets.berkeley.edu/jira/browse/CLC-4633

…and continue to camelcase front-end code:
https://jira.ets.berkeley.edu/jira/browse/CLC-3812