Add .hoverClass() and .focusClass()

Add .hoverClass() and .focusClass()

With the new CSS framework, there will be the need to add hover and focus classes to several elements.  In many cases, toggling the class will be the only logic for hovering or focusing an element.  This will require code like the following:
$(el).hover(
    function() {
        $(this).addClass('ui-state-hover');
    },
    function() {
        $(this).removeClass('ui-state-hover');
    }
);
Rather than duplicating this code over and over, I'd like to propose adding .hoverClass() and .focusClass() methods.
The above code would be replaced with:
$(el).hoverClass('.ui-state-hover');
Similarly, there would be:
$(el).focusClass('ui-state-focus');
Here is the accompanying ticket: <a href="http://ui.jquery.com/bugs/ticket/3673">http://ui.jquery.com/bugs/ticket/3673</a>