remove dependency of popover on jquery support

[shaunc]

PopoverComponent.hide has

 @$().one $.support.transition.end, => @destroy()

However jquery doc says of $.support:

Intended for jQuery's internal use; specific properties may be removed when they are no longer needed internally to improve page startup performance. For your own project's feature-detection needs, we strongly recommend the use of an external library such as Modernizr instead of dependency on properties in jQuery.support.

Perhaps a modernizr dependency would be better, and fall back if necessary to $.support?