config: removed obsolete flag for instance_id inside vcserver config.

configs/production_http.ini

@@ -15,10 +15,8 b' port = 9900'
 ##########################
 ## run with gunicorn --log-config vcsserver.ini --paste vcsserver.ini
 use = egg:gunicorn#main
-## Sets the number of process workers. You must set `instance_id = *`
-## when this option is set to more than one worker, recommended
+## Sets the number of process workers. Recommended
 ## value is (2 * NUMBER_OF_CPUS + 1), eg 2CPU = 5 workers
-## The `instance_id = *` must be set in the [app:main] section below
 workers = 2
 ## process name
 proc_name = rhodecode_vcsserver