Changes to Create a monitor

added subschema #1 subschema #2 to the response body oneOf list for the response status 422

the response's body type changed from object to no type for status 422

removed the optional property message from the response with the 422 status

added the new optional request property max_matches

removed the non-success response with the status 404

added the optional property max_matches to the response with the 201 status

added the optional property uses_current_users_monitor_cap to the response with the 201 status

endpoint added