Fix high score file not existing

Load image and sound resources correctly, can now export to runnable jar

Move files out of jar, change difficulty to an enum

Updated gitignore file

score changes

fixed a few small bugs

changed how the sounds work again, trying to make loading faster

added some sound file names

changed a few sound things, more bugs squashed

fixed a few small problems less TODOs now

amount others, remove code about ROOT, now there are no weird bullets

Added background grid, mostly working.

forgot to add player shield...

Fixed gameover, inital spawning and antialiasing setting

Started gameover, cleaned gameover and blackholes max = 4