[Feature #690] Create modalOpen and modalClose events 

Hi,

I've created two events when modal is openned or closed.
Now we can do this to listen those events : 
```
		$('#myModalexample').on('modalOpen', function(e) {
			console.log('open');
		});
		$('#myModalexample').on('modalClose', function(e) {
			console.log('close');
		});
```