Carousel: reposition itself on change of orientation

It used to be that switching from portrait to landscape (and vice
versa) would leave the carousel in between two images or on the
wrong image.

(Thanks to Donny and Helen. I'm just integrating their work.)
Making sure that move() happens with animation enabled

We disabled animation during orientationchange. Thus, we need to enable
it, in case we _programatically_ slide/move the carousel.
Do not update carousel position on window resize when only hight has changed.

window.resize event fires whenever window hight updates, we don't want to update carousel each time that happens.
Merge pull request #5 from mobify/carousel-orientation-change

Carousel: reposition itself on change of orientation