move OpenCL initialization for the unit tests in a shared header file, and support some basic command-line arguments

--cl_device=1 --cl_platform=1 --allow_opencl_cpu
add chaindemo, test for mass ratios
restore sleeping/activation mode in featherstone demo
Use _VARIADIC_MAX=10 to avoid Google Test issues with Visual Studio 2012, thanks to Mobeen for the report
Enable verbose printf for unit tests

data/init_physics.lua

@@ -21,7 +21,7 @@ maxy = 10
 toggle=1
 
 for x=0,10 do
-	for y=0,10 do
+	for y=0,5 do
 		if toggle==1 then
 			toggle = 0
 			for z=0,10 do
@@ -32,8 +32,8 @@ for x=0,10 do
 				pos = {-14+x*2,2+2*y,z*2}
 			
 				body = createRigidBody(world,shape,mass,pos,orn)
-				setBodyPosition(world,body,pos)
-				setBodyOrientation(world,body,orn)
+				--setBodyPosition(world,body,pos)
+				--setBodyOrientation(world,body,orn)
 			end
 		else
 			toggle = 1
@@ -46,7 +46,7 @@ toggle=1
 shape = createSphereShape(world, 1)
 
 for x=0,10 do
-	for y=0,20 do
+	for y=0,5 do
 		if toggle==1 then
 			toggle = 0
 		else
@@ -62,8 +62,6 @@ for x=0,10 do
 				pos = {-14+x*2,2+2*y,z*2}
 			
 				body = createRigidBody(world,shape,mass,pos,orn)
-				setBodyPosition(world,body,pos)
-				setBodyOrientation(world,body,orn)
 			end
 		end
 	end