Update gitian build descriptors to produce proper builds.

Thanks to makomk for finding the bugs here and devrandom
for passing them along (see
https://bitcointalk.org/index.php?topic=42198.msg514312#msg514312)

contrib/gitian-win32.yml

@@ -10,6 +10,7 @@ packages:
 - "unzip"
 - "nsis"
 - "faketime"
+- "wine"
 reference_datetime: "2011-01-30 00:00:00"
 remotes:
 - "url": "https://github.com/bitcoin/bitcoin.git"