void addToExternalCSS(CSSElement cssElement){
  if (externalCSS == null) {
    externalCSS=new Vector();
  }
  externalCSS.addElement(cssElement);
}

void addToExternalCSS ( CSSElement cssElement ) { if ( externalCSS == null ) { externalCSS = new Vector ( ) ; } externalCSS . addElement ( cssElement ) ; }
adds the specified csselement which represents an external css file to the external css vector
