lra73/wikibase repository overview

Result of travis build of the repo: https://github.com/l-ra/wikibase-docker⁠ which is a clone of https://github.com/wmde/wikibase-docker⁠

Modifications:

• travis build allows custom docker repo via travis env
• wdqs image is slightly modified to allow different wikibase service URL and concept URI
• docker-compose.yml is modified to run with public DNS names behind nginx with automatis crtificae enrollment using letsencrypt (https://hub.docker.com/r/jrcs/letsencrypt-nginx-proxy-companion⁠)