minor update to benchmark: use scaling for btConvexHullShape, to make sure that feature is tested.

http://bulletphysics.com/Bullet/phpBB3/viewtopic.php?f=9&t=2811

Demos/Benchmarks/main.cpp

@@ -27,9 +27,9 @@ int main(int argc,char** argv)
 	GLDebugDrawer	gDebugDrawer;
 
 //	BenchmarkDemo1 benchmarkDemo;
-	BenchmarkDemo2 benchmarkDemo;
+//	BenchmarkDemo2 benchmarkDemo;
 //	BenchmarkDemo3 benchmarkDemo;
-//	BenchmarkDemo4 benchmarkDemo;
+	BenchmarkDemo4 benchmarkDemo;
 //	BenchmarkDemo5 benchmarkDemo;
 //	BenchmarkDemo6 benchmarkDemo;
 //	BenchmarkDemo7 benchmarkDemo;