Upgrade to tzdata2012d.

This upgrade involved rewriting the script; the data has moved to ftp.iana.org,
where it's slightly less convenient to access, so it's time to use something
that can talk FTP...

As for tzdata2012d, it's just updating Morocco for this weekend's changes, now
they've been decided at the last minute (as usual).

Change-Id: I772df57a6e09b3bf3d9541bfc08930d6f18633b4
diff --git a/libc/zoneinfo/zoneinfo.version b/libc/zoneinfo/zoneinfo.version
index 9412b94..e606761 100644
--- a/libc/zoneinfo/zoneinfo.version
+++ b/libc/zoneinfo/zoneinfo.version
@@ -1 +1 @@
-2012c
+2012d