Vertex/Face/Frame duplication now draws using OpenGL display lists. Makes
drawing go much faster (2-5 times, depending on size of duplicated object).
This system uses boundbox checks too, so outside of view it draws faster.
Note for face duplication: I've fixe a bug for incorrect alignment when
the parent was rotated when a parenting happened, the 'inverse parent
correction matrix' then messed up alignment. For face duplication it now
works OK, but for vertex-dupli not... need a way to fix this backwards
compatible.