shiffman
Fixing the default scale factor
Currently, the default scale factor is set to 10. This means that 200 pixels is equal to 20 box2d meters. According to box2d docs, you should keep all objects from 0.1 to 10 meters. My pull request changes the default scale factor to 200, so that 200 pixels is equal to 1 box2d meter. This way, all of the box2d bodies are more likely to stay within the recommended size. Since I am changing the scale factor, my pull request also includes some slight changes to the QuickTest class (gravity is changed to 10.0F instead of 20.0F now that physics objects weigh less, and the simulation size is increased so that the physics objects stay within the recommended 0.1 to 10 meter range).
I also changed the step method to use a timeStep of 1.0F / parent.frameRate instead of a constant 1.0F / 60.0F, and added frameRate(60.0F); to QuickTest. This way, the physics simulation will always run at the same speed regardless of how many frames the computer is running it at. I also changed the velocity iterations to 8 and the position iterations to 3 (because these are box2d's recommended values).
