Allow to build zlib and lzma statically

This should fix issues on Darwin.

3rdparty/zlib/examples/gzip.hs

@@ -0,0 +1,8 @@
+module Main where
+
+import qualified Data.ByteString.Lazy as B
+import qualified Codec.Compression.GZip as GZip
+
+main = B.interact $ GZip.compressWith GZip.defaultCompressParams {
+                      GZip.compressLevel = GZip.BestCompression
+                    }