Converting python examples so they also run on Py3k.

Examples/Annotation/Python/DispAllFonts.py

Examples/Annotation/Python/annotatePick.py

Examples/DataManipulation/Python/FinancialField.py

Examples/GUI/Python/ImagePlaneWidget.py

Examples/GUI/Python/OrthogonalPlanesWithTkPhoto.py

Examples/Graphics/Python/SingleYoungsMaterialInterface.py

Examples/Infovis/Python/Matlab_engine_interface.py

Examples/Infovis/Python/Rinterface.py

Examples/Infovis/Python/aggregate.py

Examples/Infovis/Python/contingency_port_protocol.py

Examples/Infovis/Python/database_query1.py

Examples/Infovis/Python/databases.py

Examples/Infovis/Python/databases2.py

Examples/Infovis/Python/delimited_text_reader1.py

Examples/Infovis/Python/dimacs.py

Examples/Infovis/Python/graph1.py

Examples/Infovis/Python/merge_graphs.py

Examples/Infovis/Python/selection_domain.py

Examples/Infovis/Python/statistics_temperatures.py

Examples/Infovis/Python/streaming_statistics.py