pyInterface: convertEvtToTree update

Update convertEvtToTree to recent changes (add eventsType argument and import
core). Improve geant particle ID translation. Fix a bug where decayParticles
were not correctly identified. Add some exception handling.
pyInterface: particleDataTable python wrapper

change the python wrapper for particleDataTable to allow access to static
functions particleNameFromGeantId and geantIdFromParticleName from python.
Change convertEvtToTree.py accordingly.