Adds a listener to DOFServer that notify user of state change of a server. 
- Note
 - a listenter will only be added to a server one time. Duplicate listener will fail to be added.
 
- Parameters
 - 
  
    | self | the server to add the listener to. This must not be NULL.  | 
    | listener | the users listener to call with state change. This should not be NULL. | 
  
   
- Returns
 - TRUE if Listener was added, FALSE otherwise.
 
- See Also
 - DOFServer_RemoveStateListener