Added HAProxy discovery support #8757
Removed common-generic-clients, common-gcube-calls and common-fw-clients from dependencies
The client is not implement as gcube-proxy anymore. It is now a generic http-client (using HTTPCall class provided in API) autoquery the deprecated IS to get resource-registry instance.
Added exists() method which uses HEAD HTTP method to get existence from Resource Registry
Added API to support Entity-Relation navigation
Added API to get the list of ER types and their own schema
Added ResourceRegistryException json deserialization
Improved code quality
First Release