Automatically add copilot, PMs, and client managers #5
Description
When a new private group is created for a challenge, we need to get the challenge resources for copilot, client manager, and observers, and add them all to the group, by their username.
Assume that usernames are the same between Topcoder and Rocket.chat
Just ignore any users from Topcoder that don't currently have a user account in Rocket.chat.