Since adamw created Python client for OpenQA, we
can use it instead of calling Perl in subprocess. It simplyfies
usage and special code for running in Docker is no longer needed.
This version requires user to create configuration file either
in /etc/openqa/client.conf or in ~/.config/openqa/client.conf
with the same KEY and SECRET as in host machine.
To execute jobs in Docker, just specify correct server and
port (probably [localhost:8080]) in configuration file.
Only problem remains with self-signed certificate. It's
necessary to either disable SSL cert verifying, import
self-signed certificate or use HTTP instead of HTTPS in Docker,
see https://github.com/os-autoinst/openQA-python-client/pull/1.