gzip: build native tools from source

Recent git versions have started to call up gzip for git-archive.
However, our gzip is an MSYS program, which ends up messing up
line-endings in the binary stream between git and gzip.

Building a native gzip makes this problem go away.

Signed-off-by: Erik Faye-Lund <kusmabite@gmail.com>

src/gzip/patches/0001-use-windows-exe-prefix.patch

@@ -0,0 +1,25 @@
+From aaa5e6e398e1e4dc527df0e95c5c07e32118cb79 Mon Sep 17 00:00:00 2001
+From: Erik Faye-Lund <kusmabite@gmail.com>
+Date: Thu, 29 Sep 2011 21:55:40 +0200
+Subject: [PATCH] use windows exe-suffix
+
+---
+ Makefile.in |    2 +-
+ 1 files changed, 1 insertions(+), 1 deletions(-)
+
+diff --git a/Makefile.in b/Makefile.in
+index 40906a2..590bf8f 100644
+--- a/Makefile.in
++++ b/Makefile.in
+@@ -81,7 +81,7 @@ G=@G@
+ ZCAT=@ZCAT@
+ # To install zcat executable and man page as gzcat, use: ZCAT=gzcat
+
+-X=
++X=.exe
+ # For OS/2 or MSDOS, use: X=.exe
+
+ O=.o
+-- 
+1.7.6.355.g842ba.dirty
+

src/gzip/release.sh

@@ -0,0 +1,38 @@
+#!/bin/sh
+
+cd "$(dirname "$0")"
+
+VERSION=1.2.4
+DIR=gzip-$VERSION
+URL=ftp://ftp.cs.tu-berlin.de/pub/gnu/gzip/$DIR.tar.gz
+FILE=${URL##*/}
+
+die () {
+	echo "$*" >&2
+	exit 1
+}
+
+test -d $DIR || {
+	test -f $FILE ||
+	curl -O $URL ||
+	die "Could not download $FILE"
+
+	tar xzvf $FILE && (
+		cd $DIR &&
+		git init &&
+		git add . &&
+		git commit -m "Import of $FILE"
+	)
+} || die "Could not check out $FILE"
+
+test $(cd $DIR && git rev-list HEAD | wc -l) -gt 1 ||
+(cd $DIR && git am ../patches/*) ||
+die "Could not apply patches"
+
+(cd $DIR &&
+INSTALL=/bin/install ./configure --prefix=/mingw &&
+make &&
+index=$(/share/msysGit/pre-install.sh) &&
+make install &&
+/share/msysGit/post-install.sh $index "Install $FILE"
+) || die "Could not install $FILE"