https-test-client.py: Require --test-config parameter
https-test-client.py: Require --test-config parameter

This allows a lot of simplifications in the code, in particular it
limits the amount of parameters that influence the gnutls-cli command
to host and port.

airtower-luna/mod_gnutls,airtower-luna/mod_gnutls,airtower-luna/mod_gnutls