Add contributors in about peertube page

CREDITS.md

README.md

...c/app/+about/about-instance/about-instance.component.html

...about-peertube/about-peertube-contributors.component.html

...about-peertube/about-peertube-contributors.component.scss

...t/about-peertube/about-peertube-contributors.component.ts

...c/app/+about/about-peertube/about-peertube.component.html

...c/app/+about/about-peertube/about-peertube.component.scss

client/src/app/+about/about.module.ts

client/src/app/shared/renderer/markdown.service.ts

client/src/assets/images/framasoft.png

scripts/generate-code-contributors.ts