Add tests for whether a component is an ur or plain type definition
Add tests for whether a component is an ur or plain type definition

balanced/PyXB,pabigot/pyxb,balanced/PyXB,jonfoster/pyxb-upstream-mirror,jonfoster/pyxb1,CantemoInternal/pyxb,jonfoster/pyxb2,pabigot/pyxb,jonfoster/pyxb2,jonfoster/pyxb-upstream-mirror,balanced/PyXB,jonfoster/pyxb1,jonfoster/pyxb-upstream-mirror,jonfoster/pyxb2,CantemoInternal/pyxb,CantemoInternal/pyxb