* Returns the possible ticket agents
* @since     1.0.0
* @return   (array)     Array of users

With this function, you get all users, which can be ticket agents. This users need to have either the role administrator or ticket agent. The first users in the array are the administrators of the page. After this, a seperating string will be returned and the last users are the users with the role ticket agent.

Before the array will be returned, it will be filtered by sts-possible-agents.