WowAce

Yssaril:
    - reworked it so that there is a core which accepts filter "modules" this makes it realy easy to write new filters using the following API
    GVF.filters <-- each filter stores everything about itself here
    GVF.filters[FILTER]:AddItem(link) <-- feeds items into the filter so it knows about them
    GVF.filters[FILTER]:ClearAll() <-- removes all item info from the filter and resets the filter (is called at merchant close)
    GVF.filters[FILTER]:isFilterd(link) <-- checks to see if the current item should be displayed or filtered out
    GVF.filters[FILTER]:ResetFilter() <-- resets the filter to show all items again
    GVF.filters[FILTER]:GetDropdown() <-- called when the dropdown is opened. here each filter can register its options to the dropdown