Base on docker-playground.git's ttcn3-sgsn-test/*.cfg files, change IPs
to 127.0.0.* (keep last octet), log to stderr. The reasoning behind the
IP change is, that using almost the same IP as in the docker configs
makes it easier to compare the configs.
Change-Id: I15b5a943e9c665dfd4eb6b30bff84afc8adeb4a2