[WebBundle] Fixed some typos in skeleton config files

src/Symfony/Framework/WebBundle/Resources/skeleton/application/xml/config/config.xml

@@ -27,7 +27,7 @@
 
   <doctrine:dbal
     dbname="xxxxxxxx"
-    username="root"
+    user="root"
     password=""
   />
 

src/Symfony/Framework/WebBundle/Resources/skeleton/application/yaml/config/config.yml

@@ -10,7 +10,7 @@ web.templating:
 
 doctrine.dbal:
   dbname:   xxxxxxxx
-  username: root
+  user:     root
   password: ~
 
 doctrine.orm: ~