test plan:
* make call as account admin user, verify that channel is created
and in 'unconfirmed' state;
* make call as admin user with skip_confirmation=1 param, verify
that channel is still in 'unconfirmed' state;
* make call as site admin with skip_confirmation=1; verify that
channel is created as 'active';
* make call as any user to create a channel on your own account;
verify that call is successful;
* make call to create own channel with skip_confirmation=1; verify
that channel is still 'unconfirmed';
* make call as non-admin user to create channel for another user;
verify that 401 is returned.
Change-Id: I3108ac31b8b06f9202b9d11fa9475ed204a5f3f1
Reviewed-on: https://gerrit.instructure.com/10567
Reviewed-by: Cody Cutrer <cody@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>