SQL logging fixes

* Added user mapping on the "remote" logging database for the
administrative user. This allows calls to sys.write_sql_log() to succeed
when they are executed by code with administrative privileges.

* Added test suites for both the link to the database and the function
itself.

* Replaced RAISE NOTICE with actual logging in the universe generator

legacyworlds-server-data/db-structure/tests/user/020-extensions/010-dblink.sql

@@ -0,0 +1,23 @@
+/*
+ * Test the configuration of the dblink extension from the user's perspective
+ */
+BEGIN;
+	SELECT plan( 3 );
+	
+	SELECT diag_test_name( 'dblink - Connection' );
+	SELECT lives_ok(
+		$$ SELECT dblink_connect( 'cn_logging' , 'srv_logging' ) $$
+	);
+	
+	SELECT diag_test_name( 'dblink - Remote user = local user' );
+	SELECT is( username , current_user::TEXT )
+		FROM dblink( 'cn_logging' , 'SELECT current_user' )
+			AS ( username TEXT );
+
+	SELECT diag_test_name( 'dblink - Disconnection' );
+	SELECT lives_ok(
+		$$ SELECT dblink_disconnect( 'cn_logging' ) $$
+	);
+	
+	SELECT * FROM finish( );
+ROLLBACK;