Department of Computer Engineering, Ecole Polytechnique de Montréal, P.O. Box 6079, Station Centre-Ville, Montréal, H3C 3A7, Canada. simon.hardy@polymtl.ca|Department of Computer Engineering, Ecole Polytechnique de Montréal, P.O. Box 6079, Station Centre-Ville, Montréal, H3C 3A7, Canada. simon.hardy@polymtl.ca