Fixed classification in viewer.
Fixed classification in viewer.

Classification has apparently been broken since the switch from PySide
to PyQt4 in 35f79ec05f1cb9cbf1a869486e350e30ad879667. Some key event
code that worked with PySide did not work with PyQt.
HaroldMills/Vesper,HaroldMills/Vesper,HaroldMills/Vesper,HaroldMills/Vesper,HaroldMills/Vesper