Format comments according to VTK stlye guide

This commit fixes the comments on vtkSmartPyObject to work correctly
with Doxygen.

Change-Id: If610e661ec4f5f9718d5c48c3d9e5b06dcb3df71
Merge topic 'vtkSmartPyObject_documentation' into master

befcfd1f Format comments according to VTK stlye guide