t5100: use ancient encoding syntax for backwards compatibility

Some ancient platforms do not have an extensive list of alternate names for
character encodings.  For example, Solaris 7 does not know that ISO-8859-1
is the same as ISO8859-1.  Modern platforms do know this, so use the older
names.

The following conversions were performed:

    ISO-8859-1 --> ISO8859-1
    ISO-8859-2 --> ISO8859-2
    ISO-8859-8 --> ISO8859-8
    iso-2022-jp --> ISO-2022-JP

Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t5100/rfc2047-samples.mbox

@@ -1,48 +1,48 @@
 From nobody Mon Sep 17 00:00:00 2001
 From: =?US-ASCII?Q?Keith_Moore?= <moore@cs.utk.edu>
-To: =?ISO-8859-1?Q?Keld_J=F8rn_Simonsen?= <keld@dkuug.dk>
-CC: =?ISO-8859-1?Q?Andr=E9?= Pirard <PIRARD@vm1.ulg.ac.be>
-Subject: =?ISO-8859-1?B?SWYgeW91IGNhbiByZWFkIHRoaXMgeW8=?=
- =?ISO-8859-2?B?dSB1bmRlcnN0YW5kIHRoZSBleGFtcGxlLg==?=
+To: =?ISO8859-1?Q?Keld_J=F8rn_Simonsen?= <keld@dkuug.dk>
+CC: =?ISO8859-1?Q?Andr=E9?= Pirard <PIRARD@vm1.ulg.ac.be>
+Subject: =?ISO8859-1?B?SWYgeW91IGNhbiByZWFkIHRoaXMgeW8=?=
+ =?ISO8859-2?B?dSB1bmRlcnN0YW5kIHRoZSBleGFtcGxlLg==?=
 
 From nobody Mon Sep 17 00:00:00 2001
-From: =?ISO-8859-1?Q?Olle_J=E4rnefors?= <ojarnef@admin.kth.se>
+From: =?ISO8859-1?Q?Olle_J=E4rnefors?= <ojarnef@admin.kth.se>
 To: ietf-822@dimacs.rutgers.edu, ojarnef@admin.kth.se
 Subject: Time for ISO 10646?
 
 From nobody Mon Sep 17 00:00:00 2001
 To: Dave Crocker <dcrocker@mordor.stanford.edu>
 Cc: ietf-822@dimacs.rutgers.edu, paf@comsol.se
-From: =?ISO-8859-1?Q?Patrik_F=E4ltstr=F6m?= <paf@nada.kth.se>
+From: =?ISO8859-1?Q?Patrik_F=E4ltstr=F6m?= <paf@nada.kth.se>
 Subject: Re: RFC-HDR care and feeding
 
 From nobody Mon Sep 17 00:00:00 2001
 From: Nathaniel Borenstein <nsb@thumper.bellcore.com>
-      (=?iso-8859-8?b?7eXs+SDv4SDp7Oj08A==?=)
+      (=?ISO8859-8?b?7eXs+SDv4SDp7Oj08A==?=)
 To: Greg Vaudreuil <gvaudre@NRI.Reston.VA.US>, Ned Freed
    <ned@innosoft.com>, Keith Moore <moore@cs.utk.edu>
 Subject: Test of new header generator
 MIME-Version: 1.0
-Content-type: text/plain; charset=ISO-8859-1
+Content-type: text/plain; charset=ISO8859-1
 
 From nobody Mon Sep 17 00:00:00 2001
-Subject: (=?ISO-8859-1?Q?a?=)
+Subject: (=?ISO8859-1?Q?a?=)
 
 From nobody Mon Sep 17 00:00:00 2001
-Subject: (=?ISO-8859-1?Q?a?= b)
+Subject: (=?ISO8859-1?Q?a?= b)
 
 From nobody Mon Sep 17 00:00:00 2001
-Subject: (=?ISO-8859-1?Q?a?= =?ISO-8859-1?Q?b?=)
+Subject: (=?ISO8859-1?Q?a?= =?ISO8859-1?Q?b?=)
 
 From nobody Mon Sep 17 00:00:00 2001
-Subject: (=?ISO-8859-1?Q?a?=  =?ISO-8859-1?Q?b?=)
+Subject: (=?ISO8859-1?Q?a?=  =?ISO8859-1?Q?b?=)
 
 From nobody Mon Sep 17 00:00:00 2001
-Subject: (=?ISO-8859-1?Q?a?=
-    =?ISO-8859-1?Q?b?=)
+Subject: (=?ISO8859-1?Q?a?=
+    =?ISO8859-1?Q?b?=)
 
 From nobody Mon Sep 17 00:00:00 2001
-Subject: (=?ISO-8859-1?Q?a_b?=)
+Subject: (=?ISO8859-1?Q?a_b?=)
 
 From nobody Mon Sep 17 00:00:00 2001
-Subject: (=?ISO-8859-1?Q?a?= =?ISO-8859-2?Q?_b?=)
+Subject: (=?ISO8859-1?Q?a?= =?ISO8859-2?Q?_b?=)

t/t5100/sample.mbox

@@ -99,7 +99,7 @@ index 9123cdc..918dcf8 100644
 From nobody Sat Aug 27 23:07:49 2005
 Path: news.gmane.org!not-for-mail
 Message-ID: <20050721.091036.01119516.yoshfuji@linux-ipv6.org>
-From: YOSHIFUJI Hideaki / =?iso-2022-jp?B?GyRCNUhGIzFRTEAbKEI=?= 
+From: YOSHIFUJI Hideaki / =?ISO-2022-JP?B?GyRCNUhGIzFRTEAbKEI=?= 
 	<yoshfuji@linux-ipv6.org>
 Newsgroups: gmane.comp.version-control.git
 Subject: [PATCH 1/2] GIT: Try all addresses for given remote name
@@ -218,15 +218,15 @@ GPG-FP  : 9022 65EB 1ECF 3AD1 0BDF  80D8 4807 F894 E062 0EEA
 From nobody Sat Aug 27 23:07:49 2005
 Path: news.gmane.org!not-for-mail
 Message-ID: <u5tacjjdpxq.fsf@lysator.liu.se>
-From: =?iso-8859-1?Q?David_K=E5gedal?= <davidk@lysator.liu.se>
+From: =?ISO8859-1?Q?David_K=E5gedal?= <davidk@lysator.liu.se>
 Newsgroups: gmane.comp.version-control.git
 Subject: [PATCH] Fixed two bugs in git-cvsimport-script.
 Date: Mon, 15 Aug 2005 20:18:25 +0200
 Lines: 83
 Approved: news@gmane.org
 NNTP-Posting-Host: main.gmane.org
 Mime-Version: 1.0
-Content-Type: text/plain; charset=iso-8859-1
+Content-Type: text/plain; charset=ISO8859-1
 Content-Transfer-Encoding: QUOTED-PRINTABLE
 X-Trace: sea.gmane.org 1124130247 31839 80.91.229.2 (15 Aug 2005 18:24:07 GMT)
 X-Complaints-To: usenet@sea.gmane.org
@@ -476,7 +476,7 @@ MIME-Version: 1.0
 Content-Type: multipart/mixed; boundary="=-=-="
 
 --=-=-=
-Content-Type: text/plain; charset=iso-8859-15
+Content-Type: text/plain; charset=ISO8859-15
 Content-Transfer-Encoding: quoted-printable
 
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