Add Pull Request Template

[KeyboardInterrupt]

Add a PR Template to the repository.

[gundalow]

What fields would you like? I can add this.

[KeyboardInterrupt]

I guess this would come down to our "Quality Standards" or rather Contribution Guidelines As We have never formally laid those out, we might best start with those?
For this I would like to create a dedicated issue that allows for a discussion.

Other Awesome Lists have done similar, and I guess we could take inspiration from them i.E.:

• https://github.com/veggiemonk/awesome-docker/blob/master/.github/PULL_REQUEST_TEMPLATE.md
• https://github.com/sindresorhus/awesome-nodejs/blob/main/.github/pull_request_template.md