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.

Release 0.4.6.

1. Following options are added.
 - suppressScrollX, suppressScrollY, scrollXMarginOffset and
   scrollYMarginOffset

Release 0.4.5.

Patch notes
1. AMD compatibility.
2. Add 'useBothWheelAxes' feature.
3. Implement keyboard scrolling.
4. Implement visible rails.

Release 0.4.4.

Patch notes
1. Bug fixes.

Release 0.4.3.

Patch notes
1. Quick fix for the scrolling problem in Firefox.

Release 0.4.2.

Patch notes
1. Change the logic to detect touch devices.
2. Add minScrollbarLength setting.

Release 0.4.1.

Patch notes
1. Wrap core functionality in an each function.
2. Use scrollHeight and scrollWidth for content size.
3. IE fixes.
4. Bug fixes.

Release 0.3.4.

Patch notes
1. Fix the bug that scrollbars don't stop at the end.
2. Code refactoring.

Release 0.3.3.

Patch notes
1. Apply jshint.
2. Fix jQuery plugin site version problem.

Release 0.3.2.

Patch notes
1. Optional parameter support.
 - wheelSpeed
 - wheelPropagation
2. Example codes added.