Add an example for the scroll suppression feature.

The 'suppressScrollX' and 'suppressScrollY' features were added and
this patch add the example for the features.
Release 0.4.6.

1. Following options are added.
 - suppressScrollX, suppressScrollY, scrollXMarginOffset and
   scrollYMarginOffset
Change the names in perfect-scrollbar.jquery.json.

Change 'J' to 'j'.
Don't prevent the default scrolling for the inactive axis.