Adds CONTRIBUTING.md
Adds CONTRIBUTING.md

no more "how 2 git??? plz help" fags
M11gamer/Alien-Isolation-13,M11gamer/Alien-Isolation-13,M11gamer/Alien-Isolation-13,M11gamer/Alien-Isolation-13,M11gamer/Alien-Isolation-13,M11gamer/Alien-Isolation-13