Remove unused external-diff script.

Signed-off-by: Junio C Hamano <junkio@cox.net>

git-external-diff-script

@@ -1,67 +0,0 @@
-#!/bin/sh
-# Copyright (C) 2005 Junio C Hamano
-#
-# This script is designed to emulate what the built-in diff driver
-# does when set as GIT_EXTERNAL_SCRIPT.
-
-case "$#" in
-1)
-    echo "* Unmerged path $1"
-    exit 0 ;;
-*)
-    name1="$1" tmp1="$2" hex1="$3" mode1="$4" tmp2="$5" hex2="$6" mode2="$7"
-    case "$#" in
-    7)
-	name2="$name1" ;;
-    9)
-	name2="$8" xfrm_msg="$9" ;;
-    esac ;;	
-esac
-
-show_create () {
-    name_="$1" tmp_="$2" hex_="$3" mode_="$4"
-    echo "diff --git a/$name_ b/$name_"
-    echo "new file mode $mode_"
-    diff ${GIT_DIFF_OPTS-'-pu'} -L /dev/null -L "b/$name_" /dev/null "$tmp_"
-}
-
-show_delete () {
-    name_="$1" tmp_="$2" hex_="$3" mode_="$4"
-    echo "diff --git a/$name_ b/$name_"
-    echo "deleted file mode $mode_"
-    diff ${GIT_DIFF_OPTS-'-pu'} -L "a/$name_" -L /dev/null "$tmp_" /dev/null
-}
-
-case "$mode1" in
-120*) type1=l ;;
-100*) type1=f ;;
-.)    show_create "$name2" "$tmp2" "$hex2" "$mode2"
-      exit 0 ;;
-esac
-case "$mode2" in
-120*) type2=l ;;
-100*) type2=f ;;
-.)    show_delete "$name1" "$tmp1" "$hex1" "$mode1"
-      exit 0 ;;
-esac
-
-if test "$type1" != "$type2"
-then
-	show_delete "$name1" "$tmp1" "$hex1" "$mode1"
-	show_create "$name2" "$tmp2" "$hex2" "$mode2"
-	exit 0
-fi
-
-echo diff --git "a/$name1" "b/$name2"
-if test "$mode1" != "$mode2"
-then
-    echo "old mode $mode1"
-    echo "new mode $mode2"
-    if test "$xfrm_msg" != ""
-    then
-	echo "$xfrm_msg"
-    fi
-fi
-diff ${GIT_DIFF_OPTS-'-pu'} -L "a/$name1" -L "b/$name2" "$tmp1" "$tmp2"
-exit 0
-