Duplo (and some other) Parts

[Orion Pobursky]

Duplo will be added to the CATEGORY list.

The other 2 outliers are:

String for:
572a.dat (Update on Tracker)
572b.dat (Update on Tracker)
572c.dat
572c01.dat
572c02.dat
75924.dat
76384.dat
The updated parts use Figure Accessory

Roof for:
6121.dat
Other, similar parts use Slope.

Then there's light.dat which is on the Tracker and should probably use the new Helper class when PT functionality is implemented.