Update OpenMRS Core DockerFile

[darius (Darius Jazayeri)]

@stefan.buttigieg you’re probably better off looking at this (unless you specifically want just the platform and not the reference application):

Reference application docker image now available in dockerhub

Hi everyone, As part of migration of demo server to docker, we are now publishing reference application docker images to dockerhub: https://hub.docker.com/r/openmrs/openmrs-reference-application-distro/ There are two tags by now: 2.5 and nightly (which is more like on every build :D). The CI job to push a tag after a release was not totally tested (because I cannot do a release!), so I’d like the next release manager to get in contact with me so I’ll be available to fix the build in case that …