Updated Kubernetes configurations and added docker-compose support

[zquestz]

Additions:

• Save encrypted-dns.toml on the mounted keys volume, and make sure there is a symlink pointing to it from etc.
• Added docker-compose. This works without configuration. Just run docker-compose up. Then change the command to start, and run it again. Keys will be persisted and it can be restarted without any issues. I used port 5443 so it doesn't conflict with other services. In my env 443 is trickier to deploy when running nginx load balancers.
• Added required annotations for GCE networking policies.

Fixes https://github.com/DNSCrypt/dnscrypt-server-docker/issues/104 https://github.com/DNSCrypt/dnscrypt-server-docker/issues/94 https://github.com/DNSCrypt/dnscrypt-server-docker/issues/101

[jedisct1]

This is very cool, thank you so much for contributing this!

[mibere]

@zquestz thanks, your time and effort is honorable. But, and that's my personal opinion, @jedisct1 I really don't like it that the docker-compose.yml in this repository and project references to a foreign and "unofficial" docker image now.

[jedisct1]

Nod.

What are the differences between that external image and this one?

[zquestz]

Agreed as well. The only reason for my image is the slight change to the entrypoint.sh and Dockerfile adds a symlink. Those changes are now in your repo. You should be able to build the new image, post it on the official location and update the reference in the kubernetes and docker compose files.