Merge pull request #95 from slimakcz/patch-2

Update README.rst
diff --git a/README.rst b/README.rst
index b426099..30be47c 100644
--- a/README.rst
+++ b/README.rst
@@ -73,7 +73,7 @@
     system:
       sudo:
         enabled: true
-        alias:
+        aliases:
           host:
             LOCAL:
             - localhost