Merge pull request #92 from asiviero/master

Implement Home, End, Page Up, Page Down and Spacebar.
Add an example about the callback to check if it reaches the end.
Add a getEventClassName() function.

Each scrollbar object should have its own event class name. Unless,
When the one scrollbar is destroyed, another one's event will be
unbinded too.

The getEventClassName() function returns a unique event class name.
Release 0.4.7.

1. Don't prevent the default scrolling for the inactive axis.
2. Enhance the scrolling logic.
3. Implement Home, End, Page Up, Page Down and Spacebar for the key
   scrolling.
4. Bug fixes.
CSS fixes for IE.
Fix the bug that scrollbar rails show when they shouldn't.

Now, the scrollbar rails show even if the content is smaller than the
container. This patch fixes it.
Release 0.4.8.

1. Bug fixes.
Update jquery-mousewheel to 3.1.9
Change delta calculation in mousewheel handler.

The new version of jquery-mousewheel's delta values are changed,
and should use the new calculation for the values.
Avoid the 'divide by zero' problem in bindMobileTouchHandler.
Fixed typo in CSS: missing space in "-webkit-transition:background-color.2s linear".
Additional typo fix for the patch below.
Don't scroll by keyevent while form element has focus
Fix delta calculation in mouswheel handler

Remove division by 10, makes scrolling slower than in previous versions.
Reverts 88d286957766e981a4f4c720f213164fc0f3f099
update readme
CommonJS compatibility
create bower json and ignore bower_components directory
Add an 'Install' section in README.md
Add 'includePadding' option (use container outerWidth/outerHeight instead of width/head)
Add a description for the 'includePadding' option in README.md