GDML I/O for VecGeom Geometry Package

VecGeom is the new geometry library developed within the high-energy physics community, aiming to replace the legacy geometry navigation functionality provided by Geant4 and ROOT with optimized and vectorized algorithms. In this project we aim to develop I/O allowing to read geometry from application-independent formats such as the Geometry Description Markup Language (GDML). We propose Xerces-C as the backend to parse the files and concentrate on converting between the DOM tree and the VecGeom volume hierarchy.