Is used to command ItsNat to transport all current attributes of a client element and optionally synchronize them with the matched server element.
After synchronization the server DOM element has the same attributes and values as the client counterpart.
With or without synchronization the transported attributes can be obtained calling {@link org.itsnat.core.event.ItsNatEvent#getExtraParam(String)}
@author Jose Maria Arranz Santamaria
@see org.itsnat.core.ItsNatDocument#addEventListener(org.w3c.dom.events.EventTarget,String,org.w3c.dom.events.EventListener,boolean,int,ParamTransport[],String,long)