rem: void WMSetRulerMoveAction(WMRuler * rPtr, WMAction * action, void *clientData)
add: WMSetRulerMoveAction(WMRuler * rPtr, WMAction * action, void *clientData)
context: void WMSetRulerMoveAction(WMRuler * rPtr, WMAction * action, void *clientData){    if (!rPtr)    return;    rPtr->moveAction = action;    rPtr->clientData = clientData;}