Rewrite config with linked container env vars.
Rewrite config with linked container env vars.

ContinuumIO/docker-logstash,ContinuumIO/docker-logstash,awyrough/docker-logstash,dant3/docker-logstash,TaylorMonacelli/docker-logstash-pblittle,pblittle/docker-logstash,eternnoir/docker-logstash