[TIMOB-4613] add Ti.UI.Window.orientation property

   Titanium.UI.setBackgroundColor('#000');
   var win = Titanium.UI.createWindow({  
       title:'Test',
       backgroundColor:'#000',
   	exitOnClose: true
   });
   
   // initialize to all modes
   win.orientationModes = [
   	Titanium.UI.PORTRAIT,
   	Titanium.UI.UPSIDE_PORTRAIT,
   	Titanium.UI.LANDSCAPE_LEFT,
   	Titanium.UI.LANDSCAPE_RIGHT,
   	Titanium.UI.FACE_UP,
   	Titanium.UI.FACE_DOWN
   ]; 
   
   
   //
   // helper function
   //
   function getOrientation(o)
   {
   	switch (o)
   	{
   		case Titanium.UI.PORTRAIT:
   			return 'portrait';
   		case Titanium.UI.LANDSCAPE_LEFT:
   			return 'landscape';
   		case Titanium.UI.UNKNOWN:
   			return 'unknown';
   	}
   }
   
   //
   // get current orientation
   //
   var l = Titanium.UI.createLabel({
   	color:'#999',
   	text:'Current Orientation: ' + getOrientation(Titanium.Gesture.orientation),
   	top:10,
   	width:300,
   	height:'auto',
   	textAlign:'center'
   });
   win.add(l);
   
   //
   // orientation change listener
   //
   Ti.Gesture.addEventListener('orientationchange',function(e)
   {
   	// device orientation
   	l.text = 'Current Window Orientation: ' + getOrientation(win.orientation);
   	
   	// get orienation from event object
   	var orientation = getOrientation(e.orientation);
   	
   	Titanium.API.info("orientation changed = "+orientation+", is portrait?"+e.source.isPortrait()+", window orientation = "+ win.orientation + "is landscape?"+e.source.isLandscape());
   });
   
   win.open()