V1.4 Navigation and Fullscreen

I made a navigation update using the idea in Maselek's comment. She suggested WZ panning using the right mouse button and shift. I liked it, so I added it. There's also now a full screen option using f4. I also published the code to github, so if you have an idea you can fork it. https://github.com/Z53-INCOMING/4D-Gravity-Simulator