Added connection function to get the connection string to the server database

client/sql/0.0.1/06_geocoder_server_conn.sql

@@ -0,0 +1,16 @@
+--
+-- Geocoder server connection config
+--
+-- The purpose of this function is provide to the PL/Proxy functions
+-- the connection string needed to connect with the server
+
+CREATE OR REPLACE FUNCTION cdb_geocoder_client._server_conn_str()
+RETURNS text AS $$
+DECLARE
+  db_connection_str text;
+BEGIN
+  SELECT cdb_geocoder_client._config_get('db_server_config')->'connection_str' INTO db_connection_str;
+  SELECT trim(both '"' FROM db_connection_str) INTO db_connection_str;
+  RETURN db_connection_str;
+END;
+$$ LANGUAGE 'plpgsql';