Fix not in scope errors on ghc-7.*

ipython-kernel/src/IHaskell/IPython/Message/UUID.hs

@@ -3,6 +3,7 @@
 -- Generate, parse, and pretty print UUIDs for use with IPython.
 module IHaskell.IPython.Message.UUID (UUID, random, randoms, uuidToString) where
 
+import           Control.Applicative ((<$>), (<*>))
 import           Control.Monad (mzero, replicateM)
 import           Data.Aeson
 import           Data.Text (pack)

ipython-kernel/src/IHaskell/IPython/Message/Writer.hs

@@ -8,6 +8,7 @@ module IHaskell.IPython.Message.Writer (ToJSON(..)) where
 
 import           Data.Aeson
 import           Data.Map (Map)
+import           Data.Monoid (mempty)
 import           Data.Text (Text, pack)
 import           IHaskell.IPython.Types
 

ipython-kernel/src/IHaskell/IPython/Types.hs

@@ -35,6 +35,7 @@ module IHaskell.IPython.Types (
     extractPlain,
     ) where
 
+import           Control.Applicative ((<$>), (<*>))
 import           Data.Aeson
 import           Data.ByteString (ByteString)
 import           Data.List (find)