Jxlib jxlib → 3.2

Currently, scrolling through tabs requires clicking on the left/right arrow buttons of a Jx.Toolbar.Container.
I suggest to also support the mouse's wheel movements on the toolbar container, so that :
- scrolling the mouse's wheel upward acts like a click on the scrollLeft button, - scrolling the mouse's wheel downward acts like a click on the scrollRight button.

I don't think it's necessary to activate the tabs when scrolling (no need to fireEvent anything), but simply proxy the mouse wheel events to the scrollLeft/scrollRight buttons as click events (which may in turn fire events as needed).

Mootools has native support for the "mousewheel" event (using "mousewheel" or "DOMMouseWheel" depending on the browser). See http://mootools.net/demos/?demo=MouseWheel for more information.

The following steps can be used as a test for this feature:
1. Create a set of tabs in a TabBox so that the combined width of all the tabs is wider than the width of the TabBox's container.
2. Two buttons are automatically added (left/right arrows) to allow you to scroll through the tabs (so far, so good).
3. Try to scroll using the mouse's wheel on the bar where the tabs' names are displayed.

• why is this feature desirable? Potentially makes navigation easier. At least, makes it more inline with that of a desktop application (eg. Firefox or any other Multiple Document Interface with many open tabs).

• what components of the library are affected? Jx.Toolbar.Container

• does it change the existing API in any way? No.

• does it require documentation changes? Maybe, just add a note saying that the mouse's wheel is supported.

• does it require changes to the examples? No.