Adds properties file resolution to admin-service
Replaces NPE thrown by admin service on failed Mongo connection with actual error
Refactors library/stage configuration to be a bit more structured.
Refactors library scanning
Adds system property for setting the location of admin-service configuration.
Adds note to Admin Service readme about configuration.
Makes the ConfigurationService API clearer, adds new exception for database failures.
Merge pull request #225 from laserval/admin-service-configuration

Admin-service configuration via property file