title: Save and restore the size and position of a window in Gtk#
body: <p>I would like to save and restore the size and position of the window between program launches.
  What is the most correct and compatible way in Gtk# to:</p>
  
  <ol>
  <li>Get current size and position of the particular window.</li>
  <li>Set the size and position of the window.</li>
  </ol>