Add wheel shadows

[b]ShapeBase.h[/b]
virtual void addShadowDetail(F32 dist, F32 fogAmount, Shadow *shadow);

[b]Vehicle.h[/b]
void addShadowDetail(F32 dist, F32 fogAmount, Shadow *shadow);

[b]WheeledVehcile.h[/b]
void addShadowDetail(F32 dist, F32 fogAmount, Shadow *shadow);

[b]ShapeBase.cc[/b]
void ShapeBase::addShadowDetail(F32 dist, F32 fogAmount, Shadow *shadow)
{
   // empty stuff
}

and importantly, in 
void ShapeBase::renderShadow(F32 dist, F32 fogAmount)
{
.
.
.
[i]after this line, and before the end of this condition code, add a call to addShadowDetail [/i]
   if (mShadow->needBitmap())
   {
[b]      addShadowDetail(dist, fogAmount, mShadow);[/b]
   }
.
.
.
}


[b][vehicle.cc][/b]
void Vehicle::addShadowDetail(F32 dist, F32 fogAmount, Shadow *shadow)
{
   //empty for now
}

[b][wheeledvehicle.cc][/b]
void WheeledVehicle::addShadowDetail(F32 dist, F32 fogAmount, Shadow *shadow)
{
   Parent::addShadowDetail(dist, fogAmount, shadow);

   if ( shadow )
   {
      Wheel* wend = &mWheel[mDataBlock->wheelCount];
      for (Wheel* wheel = mWheel; wheel < wend; wheel++)
      {
         if (wheel->shapeInstance)
         {
            MatrixF mat = getRenderTransform();
            Point3F rdpos = mat.getPosition();

            // Steering & spring extension
            MatrixF hub(EulerF(0,0,mSteering.x * wheel->steering));
            Point3F pos = wheel->data->pos;
            pos.z -= wheel->spring->length * wheel->extension;
            hub.setColumn(3,pos);
            mat.mul(hub);

            // Rotation the tire to face the right direction
            // (could pre-calculate this)
            MatrixF wrot(EulerF(0,0,(wheel->data->pos.x > 0)? M_PI/2: -M_PI/2));
            mat.mul(wrot);

            // shadow details
            #ifdef LOD_WHEEL_SHADOW
            shadow->selectShapeDetail(wheel->shapeInstance, dist, 1.0f);
            #else
            wheel->shapeInstance->setCurrentDetail(0);
            #endif
            // render shadow 
            shadow->renderToBitmap(wheel->shapeInstance, mat, rdpos, Point3F(1,1,1));
         }
      }
   }
}