This commit fixes the add user drop down. Fix #826

This pull request was initiated to fix #826.

The api route "/api/<team>/users/search/?query=term&page=1" now returns all users that match given term.

This makes a lot more sense if this is a route that should be used to populate the drop-down.

If, for some security reason we need to still limit this route to only users in the given team or  access group, then we need a different route for the drop-down.

The test for this route is commented in this pull request, since I was not sure if I should change the tests. If you agree this is the way to go, I'll gladly rewrite the tests to reflect the changes.

I tested the changes in the UI and it works like a charm. Much better to find users to add to my team now.