[vtkusers] New Python package structure and widgets.

[Prabhu Ramachandran]

hi,

A few months back I committed a new package structure for the 4.x
version of the VTK-Python wrappers.  Every effort has been taken to
keep the changes backwards compatible so your old code should work
without any problems.  However, we recommend that you use the new
package structure in the future.  The package structure is documented
here:

 VTK_SRC_DIR/Wrapping/Python/README.txt

Please do read it.  All the files in the VTK_SRC_DIR/Wrapping/Python/
directory are there only for backwards compatibility.

I've also just committed 3 new widgets to CVS:

  vtk/tk/vtkTkRenderWindowInteractor.py

  vtk/gtk/GtkVTKRenderWindowInteractor.py

  vtk/wx/wxVTKRenderWindowInteractor.py

They are all based on the new vtkGenericRenderWindowInteractor class.
These new classes should enable you to use the new 3DWidgets from
Python.  Again, I have chosen to add these as new widgets in order to
keep older code working as before.

I've no experience with pyQt so haven't created the Qt interactor
widget.  Since no one has volunteered to add it I'll try and add it
sometime later.

Please report bugs/issues/suggestions to the lists (vtkusers and
vtk-developers at public.kitware.com).

prabhu