Merge pull request #1194 from PyBossa/fix-typo-nginx

fix typo in nginx docs

Author: therealmarv

Diff for: doc/nginx.rst

@@ -129,7 +129,7 @@ Configure Redis and sentinel as service with supervisord
 
 First stop redis service and all running redis instances with::
 
-  sudo server redis-server stop
+  sudo service redis-server stop
   killall redis-server
 
 We want to run redis and sentinel with supervisord because supervisord is more