authtype_list
Description:
Parameters:
| include_plain | 
           whether or not to include the PLAIN mechanism  | 
      
Returns:
| 
           a List of SASL-supported authtypes. The caller must free the list, but not the contents.  | 
      
| include_plain | 
           whether or not to include the PLAIN mechanism  | 
      
| 
           a List of SASL-supported authtypes. The caller must free the list, but not the contents.  |