[Pyode-user] Small bug in Tutorial 3

[<Tho...@di...>]

Hi,

the pyode tuts are a charming way to make first contact, but at tutorial 
three, I wasn't sure exactly _what_ I was seeing, until I replaced
glutInitDisplayMode (GLUT_RGB | GLUT_DOUBLE)
with
glutInitDisplayMode (GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH)
for the obvious reasons :-).

Regards,
    Thomas