import Data.Time.Clock to build with time-1.9.1

In more recent versions Data.Time exports secondsToNominalDiffTime etc,
but originally it did not.

Author: joeyh

Utility/TimeStamp.hs

@@ -17,6 +17,7 @@ module Utility.TimeStamp (
 import Utility.Data
 
 import Data.Time.Clock.POSIX
+import Data.Time.Clock
 import Data.Time
 import Data.Ratio
 import Control.Applicative