MINIFICPP-2766 Preventing C++ exceptions from unwinding the stack ove…

[cccs-jsjm]

…r the Python interpreter.

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[szaszm]

Thank you for your contribution!

At first glance, your changes seem to do what they're supposed to: catch C++ exceptions, and translate them to Python exceptions. 👍

I'm not sure what happens if no Python stack frame catches the Python exceptions. In that case, letting the exception continue to unwind the C++ stack frames, and eventually rollback the flow file would probably be a better error handling, than letting it become an unhandled Python exception, whatever behavior that means. I didn't test this yet. We may need to change that later.

I'd also like to wait for the feedback of @lordgamez, since he has worked quite a bit on the python processor API, he has more insight into the gotchas with python bindings. I'm expecting him to be able to get to this sometime next week, after easter.