add convenience function to report which etree OWSLib is using (#276)
add convenience function to report which etree OWSLib is using (#276)

KeyproOy/OWSLib,tomkralidis/OWSLib,mbertrand/OWSLib,geographika/OWSLib,ocefpaf/OWSLib,kwilcox/OWSLib,kalxas/OWSLib,JuergenWeichand/OWSLib,Jenselme/OWSLib,QuLogic/OWSLib,geopython/OWSLib,bird-house/OWSLib,jachym/OWSLib