THRIFT-901. hs: Allow the bindings to compile without -fglasgow-exts and with -Wall -Werror

This patch makes the bindings compile with pedantic warning levels, and individually declares each required language extension.

Patch: Christian Lavoie

git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@998955 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/lib/hs/src/Thrift/Transport.hs b/lib/hs/src/Thrift/Transport.hs
index 80e4914..99dbd6f 100644
--- a/lib/hs/src/Thrift/Transport.hs
+++ b/lib/hs/src/Thrift/Transport.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE DeriveDataTypeable #-}
 --
 -- Licensed to the Apache Software Foundation (ASF) under one
 -- or more contributor license agreements. See the NOTICE file
@@ -39,7 +40,7 @@
     tFlush  :: a -> IO ()
     tReadAll :: a -> Int -> IO LBS.ByteString
 
-    tReadAll a 0 = return mempty
+    tReadAll _ 0 = return mempty
     tReadAll a len = do
         result <- tRead a len
         let rlen = fromIntegral $ LBS.length result