jep exceptions include full python traceback and/or java stacktrace

This changeset makes JepExceptions include the entire Python traceback and Java Stacktrace, depending on where the original error was thrown.

This perhaps need to be more configurable as some applications may not want to include either trace while other applications will require full traces to properly diagnose and fix bugs.
Presumably?  I'm not a C expert.  Code was taken from:  http://bugs.python.org/issue563338
http://bugs.python.org/file497/py_traceback.c