Create contributing file [CI skip]
Create contributing file [CI skip]

It was based on this contributing file:
https://github.com/sharelatex/sharelatex/blob/master/CONTRIBUTING.md

MicroPasts/micropasts-crowdfunding,gustavoguichard/neighborly,MicroPasts/micropasts-crowdfunding,gustavoguichard/neighborly,gustavoguichard/neighborly,MicroPasts/micropasts-crowdfunding,MicroPasts/micropasts-crowdfunding