Add of 'beforeSlideChange' method

[chienrouge]

Just to be able to call a custom method when the new element is about to slide in.

[jakobholmelund]

Hmm could this be implemented with :once ?

[jakobholmelund]

Altso needs to be updated with newest master

[chienrouge]

Hi there.
you're perfectly right. will do so straight away :)

[RiZKiT]

I'm not sure why you use an event, try the following, should work fine (the first line is the only interesting one, the others are just to show the position):

...
self.options.beforeSlideChange(activeSlide.get("morph"));
activeSlide.get("morph").start(morphOptions).chain(function(){
    self.slides[prevActiveSlideIndex].setStyle("z-index", 1);
    self.unlock();
    self.options.afterSlideChange(this);
});
...

and if you already modify the options, please add the following (you may change the name morphFx):

...
    beforeSlideChange: function(morphFx){},// empty function
    afterSlideChange: function(morphFx){}// empty function
...