Updates Nov 3

Iv done a few major things: 

- Created a Screen class that is a type for all screens (GameScreen, OptionsScreen, etc) to extend in order to be able to use them all casted as (Screen) this is useful when having a getScreen method in the SpaceInvadersGame.java code, where I need a return value, and all the screens before were completely different classes. This works great: public static Screen getScreen() { return this.frame.getComponent(0); }
    Also with this came the setScree() and all for switching screens in the course of the game application

- Created a GameObject class for all gameObjects to extend. Has easy parameters to work with

- Added a little test display in GameScreen (spaceship floating in the center