Linux Support Integration

You no longer have to unpack a seperate Linux.zip file. A shell script is now in the main folder!
From here on is the v0.9.3 changelog:

Reworked

Score System:
- now called Research System
- you get more research the closer you fly to the planet (fly safe though... pls ._.)
- planets have custom research multipliers
- research gets added every second
- research needs to be flown back to the home base to be stored
- research not stored in your home base will get lost upon death/reset
- stored research gets saved to a json file upon closing the game using the "QUIT" button on the main menu (will be useful in coming updates)
Planet Data Storage:
- planet data is being stored in a json file
- can support up-to 10 planets
- custom planets are possible (game-breaking ones too!! :D)
Settings Data Storage:
- settings stored in a json file, which is been read from at game start (saving isn't possible at this moment so you have to manually edit the json-file to save settings)

Planet Atmospheres:
- slow you down drastically if you fly too close
Sprites/Textures:
- planet features
- home base
Music:
- title screen music
- ambient music
Soundeffects for buttons
Credits screen
Settings:
- separation into Visual / Controls and Sound Settings
- even more setting options! :D
Bugs (probably)

Bugs:
- shield and explosion not showing up
- removed fullscreen option on game window
- player taking multiple damage from one collision (added invincibility frame)