docs: update sidenav-width-adjust script so Training classes save the width...

  if (sidenav.length) { // Must check if the nav exists because IE6 calls resizeWidth() from resizeAll() for all pages

    var basePath = getBaseUri(location.pathname);

    var section = basePath.substring(1,basePath.indexOf("/",1));

    section = section.indexOf("training") != -1 ? "resources" : section;

    writeCookie("width", sidenavWidth, section, null);

  }

}