Cleanup repo

[AntoineRondelet]

I am wondering whether it would be cleaner to add all community related files (contribution, issue/PR templates and so on) under .github like https://github.com/docker/cli/tree/master/.github or https://github.com/ethereum/go-ethereum/tree/master/.github for instance.

Looking at the current state of the repo, it looks like many images are in this .github folder. We could do something like .github/images and put these images into it, and have the contribution files under .github directly.

What do you think @zoenolan ?

[zoenolan]

I was definitely thinking the issue and pull request templates #62 should live in .github

[zoenolan]

i think thus is mostly done now with #67