Enable customization of the Task Switcher items

[GoogleCodeExporter]

This would likely take some work in the menu side of the system.  It would be 
great to be able to customize what is available on the Task Switching system.  
It seems it might make most sense to do it via the menu manager.  Either a 
hidden menu category, or perhaps more preferred would be a new property on each 
menu entry for 'Include in Task Switcher'.

As a bonus, it would be great to add an icon property to each menu item.  The 
current theme/menu style wouldn't use it, but that's not to say it wouldn't be 
used in future menu styles, and it could certainly be used for the task 
switcher system.

Original issue reported on code.google.com by [email protected] on 2 Jan 2013 at 3:06