Fix PostgreSQL scaffolding

yesod/scaffold.hs

@@ -111,6 +111,10 @@ scaffold = do
           MongoDB    -> $(codegen $ "mongoDBConnPool")
           Tiny       -> ""
 
+        textImport = case backend of
+          Postgresql -> ", concat, append, snoc, pack"
+          _          -> ""
+
         packages = if backend == MongoDB then "          , mongoDB\n         , bson\n" else ""
 
     let fst3 (x, _, _) = x

yesod/scaffold/config/Settings.hs.cg

@@ -32,7 +32,7 @@ import Yesod (liftIO, MonadControlIO, addWidget, addCassius, addJulius, addLuciu
 import Data.Monoid (mempty, mappend)
 import System.Directory (doesFileExist)
 import Prelude hiding (concat)
-import Data.Text (Text)
+import Data.Text (Text~textImport~)
 import Data.Object
 import qualified Data.Object.Yaml as YAML
 import Control.Monad (join)