ECL-195
Service discovery for the UIS client

added Zookeeper properties in the properties file
ECL-195
Service discovery for the UIS client

First version of the service discovery with zookeeper, the UIS client
queries zookeeper directly
ECL-195
Service discovery for the UIS client

added logging message for the UrlProvider()
Merge branch 'master' of https://github.com/europeana/Europeana-Cloud.git