title: I am unable to reference QSettings using Qt
body: <p>I am running a project that uses Qt. I have installed version 5.10.1 (msvc2017_64). I receive an error that the <code>QSettings</code> is undefined. I cannot find the reference in the libraries installed.</p>
  
  <pre><code>#include "mainwindow.h"
  #include &lt;QtWidgets/QApplication&gt;
  
  
  int main(int argc, char *argv[])
  {
      QApplication a(argc, argv);
      QCoreApplication::setApplicationName("Circuit Editor");
      QSettings settings;
      MainWindow w;
      w.setWindowTitle("Circuit Editor");
      w.show();
  
      return a.exec();
  }
  </code></pre>