[NEW SHAKE PROPERTIES] Added a ShakeGenericTweenProperty class to allow shaking any kind of prop.

Added corresponding entries in GoTweenConfig ( shakeFloatProp, intFloatProp, etc…).

This is a quite elegant way to add a lot of shake options with only one new tween property class. I have the feeling that referencing a tween property inside another tween property opens the way to new range of powerful tween properties, but not sure yet exactly how this can be exploited and for what precise goal.

Note that I've tested only the shakeFloatProp(...) method but I don't see why other methods wouldn't work.