transitionend event patch

1. transitionend event patch

> Sometimes the transition end event is triggered before touchend, which
froze the slider. Force trigger it after transition end, after touchend.

2. touch sensitivity

> Set to a certain number, rather than a percentage of the width of
slider. The latter one could be too insensitive if the width is large.

3. indentation

> Fixed some indentation problem which got stuck while compiling.