[vtkusers] vtkFLTK release 0.5.0

[Sean McInerney]

The 0.5.0 release of vtkFLTK features some minor API changes as well as 
simplification of the implementation. vtkFLTK now depends on FLTK 
version >= 1.1.0 and VTK version >= 4.1.0. The elimination of backwards 
compatibility code for FLTK 1.0.x and VTK 3.2.x simplifies the 
implementation and should improve maintainability. These changes 
coincide with the creation of an experimental vtkFLTK branch for use 
with FLTK2. Additionally, the 'Simple' example has been added and 
demonstrates simple VTK animation via timeouts.