1.2.4 - change naming of some apis.

Here are a list of the props that are changed:

afterChanged -> afterChange
disableSwipeOnMobile -> swipeable
forSSR -> ssr
disableDrag -> draggable
removeArrow -> arrows
shouldShowDots -> showDots
contentClassName -> sliderClass
itemClassName -> itemClass
containerClassName -> containerClass
dotListClassName -> dotListClass