Add dockerfile and build/run instructions

[mauritsvdvijgh]

PR contents

• Adds dockerfile with build and run stage
• Adds some instructions on how to docker build/run
• Fixes typo in readme

Key Dockerfile related points

• From scratch for the runtime image resulting in <10mb image size
• Dynamically linked libraries (using the normal build.sh script) but copying the used libraries to an empty (scratch) image
• Container will run with app specific user/group (not root)
• Uses current debian stable as builder image

Let me know if there are things you would like to see changed and I will update the PR!

After this a nice step would be to have CI build the image, publish it to a public docker registry. Then you can update the website/readme with a docker run one-liner so people can easily try this out.

[halfgaar]

Thanks!

I reworked it a little and added some extra info to the readme, but I merged it. I can't use the Github merge interface anymore, so I'll just close the PR...