Add some more Data.Functor functions; fixes #7817

Added infixl4 $>.
Re-exported void from Data.Functor.
Also defined the fixity for <$ for non-GHC impls.

Data/Functor.hs

@@ -18,12 +18,19 @@ module Data.Functor
     (
       Functor(fmap),
       (<$),
+      ($>),
       (<$>),
+      void,
     ) where
 
+import Control.Monad
 #ifdef __GLASGOW_HASKELL__
 import GHC.Base (Functor(..))
-#else
+#endif
+
+#ifndef __GLASGOW_HASKELL__
+infixl 4 <$
+
 (<$) :: Functor f => a -> f b -> f a
 (<$) =  fmap . const
 #endif
@@ -34,3 +41,8 @@ infixl 4 <$>
 (<$>) :: Functor f => (a -> b) -> f a -> f b
 (<$>) = fmap
 
+infixl 4 $>
+
+($>) :: Functor f => f a -> b -> f b
+($>) = flip (<$)
+