Add 'loaded' callback to modal dialog

Created by: tanraya

I think it is a good idea to add 'loaded' callback to modals. Something like that:

    this.options.remote && this.$element.find('.modal-body').load(this.options.remote, $.proxy(function() {
      this.$element.trigger('loaded')
    }, this))

Here's complete code https://gist.github.com/3486192 I can make pull request if this functionality is really needed.