title: sensorGroup and sensorMask combination for ships and bullets in Nape
body: <p>I have multiple spaceships (<code>SHIP_CB</code> CbType), that can all shoot missiles (<code>BULLET_CB</code> CbType). How do I set up there <code>sensorGroup</code>, <code>sensorMask</code> and <code>InteractionListeners</code> so I get the following behaviour:</p>
  
  <ol>
  <li>Ships all collide and bounce off each other.</li>
  <li>Bullets don't react or sense each other at all.</li>
  <li>Bullets sense with Enemy Ships.</li>
  <li>Bullets <strong>do not</strong> sense with the Ship who shot the bullet.</li>
  </ol>
  
  <p>Is it even possible to get all these behaviours just by setting the correct sensorGroup and sensorMask on each object?</p>