Reviving BulletD -- again

[BLM768]

> Why a port instead of a wrapper?

I initially tried to generate a wrapper with SWIG, but Bullet 
uses nested classes, which cause SWIG to choke. I could write my 
own wrapper, but it would cause a loss of flexibility (especially 
with templates) and introduce a bit of overhead. Considering the 
size of Bullet's interface, a port doesn't seem that much harder 
than a wrapper when both languages use a similar syntax.

That being said, if anyone has an idea for a wrapper system that 
would expose all or most of what can be done with the C++ 
interface and be significantly easier to maintain than a port, 
I'm completely open to the idea.