Support/Documentation for client certificates removed. Even if kuksa-client supports it there is no reason to use it as Databroker/Server cannot be configured to check client certificates.
In integration tests we explicitly specify that we want an insecure connection. Not strictly needed now, but good if we later change default in Databroker
This is a companion PR to https://github.com/eclipse/kuksa.val/pull/580
It cannot be merged as the other PR first must be merged, then a pypi package created which can be referenced from this PR
(Edit: a Kuksa-client prerelease ahs been created matching the PR at https://pypi.org/project/kuksa-client/0.4.0a3/)
Design principles: