title: force refresh of external libraries not working
body: <p>I have python project within a virtualenv. I opened it in pycharm.</p>
  
  <p>Later i have installed some packages using pip from inside the virtualenv but not from pycharm rather from the commandline directly.</p>
  
  <p>But in pycharm > settings > python interpreter : it does not show the package which i just installed from outside pycharm.</p>
  
  <p>I tried to select another interpreter and come back, still its not showing the package installed from outside pycharm. </p>
  
  <p>I have restarted pycharm still no luck.</p>
  
  <p>Any idea how to refresh python packages inside pycharm</p>