added ag::drawObjects() to draw all objects in the scene from a lua script

git-svn-id: svn://anubis/anaglym/trunk@65 99a6e188-d820-4881-8870-2d33a10e2619

tests/ballstairs.lua

@@ -4,11 +4,7 @@ function update()
     ag.setCamera(7, -6, 15, ballx, bally, ballz, 0, 0, 1)
     ag.doPhysics()
     ag.startFrame()
-    arena:draw()
-    ball:draw()
-    ball2:draw()
-    ball3:draw()
-    logo:draw()
+    ag.drawObjects()
     ag.endFrame()
 end