Add support to Event Emitter to sld/html/Element

Now you can make like this
```javascript
parser.parse({
    $type : 'sld/html/Element',
    tagName : 'input',
    type : 'button'
}).then(function(button) {
    // this now work
    on(button, 'click', function() {  console.log('It\'s works!!') });

})