title: prompt before exit program in TideSDK/TideKIT
body: <p>I was looking for a way to tell the app to confirm if you really want to close the app before losing the changes of the project. </p>
  
  <p>Through the current API, I was not able to do it. Looking on how Air/Flex do that, it looks like an event listener of the window when closing:</p>
  
  <pre><code>&lt;s:WindowedApplication xmlns:fx="http://ns.adobe.com/mxml/2009" 
                     xmlns:s="library://ns.adobe.com/flex/spark" 
                     xmlns:mx="library://ns.adobe.com/flex/mx"
                     maxHeight="1080"
                     maxWidth="1920"
                     minWidth="1280"
                     minHeight="720" 
                     showStatusBar="false" 
                     creationComplete="startUp()"
                     closing="closeWindow(event)"
                     &gt;
  </code></pre>
  
  <p>when I close the window through the Window interface or through the application menu, it executed what I was expecting, a prompt before the window close </p>
  
  <pre><code>Do you want to exit the application?/Do you want to exit without saving changes?
  yes no.
  </code></pre>
  
  <p>Do TideSDK/TideKIT have this behavior? if so, please attach an example. It is very important for me to understand how to do it properly.</p>
  
  <p>Thanks.</p>