merge PR NobleRobot#63: fix background not drawing on scene transitions

Author: assada

modules/NobleScene.lua

@@ -138,6 +138,7 @@ function NobleScene:enter() end
 --
 function NobleScene:start()
 	Noble.Input.setHandler(self.inputHandler)
+	Graphics.sprite.redrawBackground()
 end
 
 --- Implement to run scene-specific code on every frame while this scene is active.
@@ -239,4 +240,4 @@ function NobleScene:pause() end
 --		YourSceneName.super.resume(self)
 --		--[Your code here]--
 --	end
-function NobleScene:resume() end
+function NobleScene:resume() end