use cElementTree if available and renamed klass to upnp_class
use cElementTree if available and renamed klass to upnp_class

opendreambox/python-coherence,opendreambox/python-coherence,sreichholf/python-coherence,coherence-project/Coherence,sreichholf/python-coherence,unintended/Cohen,ismaelgaudioso/Coherence,furbrain/Coherence,coherence-project/Coherence,unintended/Cohen,ismaelgaudioso/Coherence,furbrain/Coherence