[ODE] ODE .NET binding

[Jason Perkins]

FYI...

I've started working on a .NET binding for ODE that doesn't require
managed C++ or unsafe code. In order to demonstrate the binding I had
to make some modifications to Drawstuff to allow it to be build as a
DLL. Right now I am working in the svn branch `branches/ode.net`.
After 0.7 is released I will merge my changes back to the trunk.

I have updated the windows build scripts (in the branch) to create a
drawstuff.dll, but I have no idea how to modify the autotools scripts.
If someone can give me a clue I can attempt the changes there as well.

Thanks!

Jason