mapedit work

-finished support for converting item to overlay
-fixed persistent issue where ghost overlay was not drawing
-fixed preserved rotation issue
-added support for displaying converted overlay in listbox
-tweaked drawing new overlays to look like ghosting rects
-fixed saving converted overlay issue
-fixed some poi glitches/streamlined things
-added button to place a new overlay
-added button to toggle overlays
-added button to toggle pois
-changed some button action fcns