[skip ci] Clarification about name arg

Author: Jamie Hannaford

docs/getting-started-openstack.md

@@ -48,8 +48,7 @@ In this case, we want to use the Nova service:
 $compute = $client->computeService('nova', 'regionOne');
 ```
 
-The first argument is the __name__ of the service as it appears in the OpenStack service catalog. If in doubt, you can
-leave blank and it will revert to the default name for the service. The second argument is the region. The third and
+The first argument is the __name__ of the service as it appears in the OpenStack service catalog. For OpenStack users, this must be retrieved and entered in your code. The second argument is the region. The third and
 last argument is the type of URL; you may use either `publicURL` or `internalURL`.
 
 ### 3. Select your server image
@@ -187,4 +186,4 @@ $server->delete();
 Consult our [documentation](https://github.com/rackspace/php-opencloud/tree/master/docs/userguide) about other services
 you can use, like [Keystone](https://github.com/rackspace/php-opencloud/tree/master/docs/userguide/Identity) or
 [Swift](https://github.com/rackspace/php-opencloud/tree/master/docs/userguide/ObjectStore). If you have any questions or
-troubles, feel free to e-mail [email protected] or open a Github issue with details.
+troubles, feel free to e-mail [email protected] or open a Github issue with details.