Added an argument "0" when calling the "item" method on the
changedTouches of a mobile touch event.
1. Changed the transition duration for scrolling once to 500
milliseconds.
2. Added a factory method which returns an instance of the
com.huanli.ui.ScrollBars class. In this way the accidental missing of
the "new" operator can be avoided which eliminates some weird problems.
3. Refactored the parameters for controlling the display of the scroll
bars.
4. Added a pair of parameters for controlling whether the horizontal and
the vertical scrolling is enabled or not for both the X and the Y axes.
5. Added a parameter for switching between regular scrolling and
scrolling by pages.
6. Added a parameter for switching on and off the functionality of
scrolling by mouse wheel.
7. Added a parameter for toggling the display of the resize knob.
8. Added a parameter for customizing the color of the scroll bars.
9. Replaced some mandatory styles which were applied by adding CSS
classes with inline CSS styles. This will enforce the application of
these styles.
10. Added a function for adding CSS transition properties for scrolling
by pages functionality.
11. Removed the code which remembered the styles of the to be wrapped
element and applied them to the wrapper element.
12. Corrected the effect of the "bAutoHide" parameter.
Renamed the ScrollBars to kScroll
Added a interface for adding an event handler "onWrappeeScrolled" which
will be invoked after the wrapped element has just been scrolled.

Signed-off-by: Huan Li <klx211@gmail.com>
Added a parameter in the configuration object for registering event
handlers for the events including 'scrolled', 'endReached',
'topEndReached', 'rightEndReached', 'bottomEndReached', and
'leftEndReached'. The event handlers can also be specified after the
instance of the com.huanli.ui.KScroll class is created by adding
corresponding event handler functions to the instance.

Signed-off-by: Huan Li <klx211@gmail.com>