Remove the item and associated nodes. It appends the item to the ICNDocument's delete list, so you must call ICNDocument::flushDeleteList() after calling this (and possible ICNDocument::clearDeleteList() befor calling it) The virtual function void handleRemove() is called to allow any child classes to clear up any neccessary data (which doesn't do anything by default), before CNItem does the rest
Reimplemented from CNItem.
Reimplemented in ECSubcircuit.
Referenced by ECSubcircuit::removeItem().