add postgrest redme

openshift/templates/postgrest/readme.txt

@@ -0,0 +1,12 @@
+== Postgrest research on test env
+create role web_anon nologin;
+  # GRANT CONNECT ON DATABASE cthub TO web_anon;
+GRANT USAGE ON SCHEMA public TO web_anon;
+GRANT SELECT ON public.vehicle TO web_anon;
+  # ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES TO web_anon;
+create role authenticator noinherit login password 'xxxxx';
+GRANT web_anon to authenticator;
+
+select * from information_schema.role_table_grants where grantee='web_anon';
+
+openssl rand -hex 64