[ODE] Simple avatar setup

[Megan Fox]

Just one thing I wanted to point out - if you set friction to 0 for
your player avatar, and you're designing a game with any level of
physical interaction (eg. can boxes be thrown at you?  Will you be
pushing things around?), you'll find things ricochet off the player in
extremely bizarre fashion.  She'll just slide off boxes to the side
instead of looking as if she's pushing them, and so on.

Solution - use the second method, the floating "whatever" (sphere,
ccylinder, box, geom group, whatever suits your fancy), and tweak the
friction of the player body visually through a bit of target practice
with thrown objects.

(or maybe special-case the floor/player collision to be frictionless
while everything else stays the same, but I prefer consistent rules
when I can get them)

-Megan Fox

> Set friction to 0 (use frictionless contacts) to avoid
> jumpyness.