Fix for recusion limit hit for _rake_command alias

plugins/rails/rails.plugin.zsh

@@ -6,7 +6,7 @@ function _rails_command () {
   elif [ -e "script/server" ]; then
     ruby script/$@
   else
-    rails $@
+    command rails $@
   fi
 }
 
@@ -14,7 +14,7 @@ function _rake_command () {
   if [ -e "bin/rake" ]; then
     bin/rake $@
   else
-    rake $@
+    command rake $@
   fi
 }