title: Sort a map on key and value
body: <p>I want to sort a Map on key and value. First on key then on value.
  For example, this should be the result;</p>
  
  <p><code>1,2
  1,3
  2,1
  2,2</code></p>
  
  <p>Anyone has a suggestion on how to achieve this effectively? I've been seeing people using a TreeMap to sort keys, however i also need values.</p>
  
  <p>Or ofcouse any other method of sorting pairs on key and value is welcome.</p>