user32: Implement support for HBMENU_POPUP_* magic menu bitmaps and use them to decorate the system menu.

fusion: Use parsed properties for assembly enumeration instead of trying to parse the display name again.

The display name passed in may not be normalized, e.g. if the version number
is passed as "1.0.0.00000" instead of "1.0.0.0". This patch should also cut
down on case insensitive file searches.