#54: Documented JW.Updater.
#54: Added JW.Switcher. Documented JW.UI.AttrUpdater.
#54: Documented JW.UI updaters and listeners.
#54: Documentation fixes.
#54: Tested JW.Property.
#54: Tested JW.Class.own.
#54: Tested JW.Proxy. Fixed bug.
#54: Tested JW.AbstractCollection.ownItems.
#54: Tested JW.Copier.
#54: Tested JW.Updater. Fixed bug.
#54: Tested JW.Updater. Fixed bug.
#54: Tested JW.Functor.
#54: Tested JW.Switcher.
#54: Removed $ dependency. Extended JW.UI.ValueListener sensitivity. Added demo to the home page.