sanity checks 0.19

Please do sanity checks according to steps below:

1. Get the tarball and check it, run tests. tarball: https://gitlab.isc.org/isc-projects/stork/-/jobs/1914859/artifacts/browse
2. Start demo locally with rake docker_up and follow the steps from the demo wiki: https://gitlab.isc.org/isc-projects/stork/-/wikis/Demo
3. Install server and agent locally e.g. in VMs from binary debs & rpms packages: https://gitlab.isc.org/isc-projects/stork/-/jobs/1914860/artifacts/browse