fix(nginx): switch to nginx -s reload to reload nginx configuration

no issue
- this is a more graceful reload command that doesn't do a hard restart of nginx

Author: acburdine

extensions/nginx/index.js

@@ -238,7 +238,7 @@ class NginxExtension extends cli.Extension {
     }
 
     restartNginx() {
-        return this.ui.sudo('service nginx restart')
+        return this.ui.sudo('nginx -s reload')
             .catch((error) => Promise.reject(new cli.errors.ProcessError(error)));
     }