TextFieldTextRenderer: fixed issue where snapshot wasn't updated after isEnabled change
TextFieldTextEditor: fixed issue where snapshot wasn't updated after isEnabled change
ScrollBar: hides thumb when disabled
AeonDesktopTheme: fixed some issues with disabled components
Themes: some more tweaks to disabled skinning
IPopUpContentManagers: dispatch Event.OPEN when opened to go with Event.CLOSE when closed
PickerList: better handling of toggle button
MetalWorksDesktopTheme: updates for disabled skins and some missing skins (references #528)