VisualPinball now shows a dialog on Python failure

0. Added the ability to track if the game has crashed and respond to successive COM calls with a COMException.  The end result is that Visual Pinball will show a dialog box on Python failure, and the dialog actually tells you where in the Python the code crashed.

1. Last version added stack traces to the logs on failure, but they were poorly formatted.  Now they are nicely formatted.