Fix bug that range in canvas constructor was ignored; label takes numeric; experiment scene.hasmouse
Fix bug that range in canvas constructor was ignored; label takes numeric; experiment scene.hasmouse

mwcraig/vpython-jupyter,mwcraig/vpython-jupyter,BruceSherwood/vpython-jupyter,sspickle/vpython-jupyter,sspickle/vpython-jupyter,BruceSherwood/vpython-jupyter,mwcraig/vpython-jupyter,BruceSherwood/vpython-jupyter,BruceSherwood/vpython-jupyter,mwcraig/vpython-jupyter