send-email: also pick up cc addresses from -by trailers

When rerolling a patch series, including various Reviewed-by etc. that
may have come in, it is quite convenient to have git-send-email
automatically cc those people.

So pick up any *-by lines, with a new suppression category 'misc-by',
but special-case Signed-off-by, since that already has its own
suppression category. It seems natural to make 'misc-by' implied by
'body'.

Based-on-patch-by: Joe Perches <joe@perches.com>
Signed-off-by: Rasmus Villemoes <rv@rasmusvillemoes.dk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/git-send-email.perl b/git-send-email.perl
index 1916159..58c6aa9 100755
--- a/git-send-email.perl
+++ b/git-send-email.perl
@@ -94,7 +94,7 @@
     --identity              <str>  * Use the sendemail.<id> options.
     --to-cmd                <str>  * Email To: via `<str> \$patch_path`
     --cc-cmd                <str>  * Email Cc: via `<str> \$patch_path`
-    --suppress-cc           <str>  * author, self, sob, cc, cccmd, body, bodycc, all.
+    --suppress-cc           <str>  * author, self, sob, cc, cccmd, body, bodycc, misc-by, all.
     --[no-]cc-cover                * Email Cc: addresses in the cover letter.
     --[no-]to-cover                * Email To: addresses in the cover letter.
     --[no-]signed-off-by-cc        * Send to Signed-off-by: addresses. Default on.
@@ -454,13 +454,13 @@
 if (@suppress_cc) {
 	foreach my $entry (@suppress_cc) {
 		die sprintf(__("Unknown --suppress-cc field: '%s'\n"), $entry)
-			unless $entry =~ /^(?:all|cccmd|cc|author|self|sob|body|bodycc)$/;
+			unless $entry =~ /^(?:all|cccmd|cc|author|self|sob|body|bodycc|misc-by)$/;
 		$suppress_cc{$entry} = 1;
 	}
 }
 
 if ($suppress_cc{'all'}) {
-	foreach my $entry (qw (cccmd cc author self sob body bodycc)) {
+	foreach my $entry (qw (cccmd cc author self sob body bodycc misc-by)) {
 		$suppress_cc{$entry} = 1;
 	}
 	delete $suppress_cc{'all'};
@@ -471,7 +471,7 @@
 $suppress_cc{'sob'} = !$signed_off_by_cc if defined $signed_off_by_cc;
 
 if ($suppress_cc{'body'}) {
-	foreach my $entry (qw (sob bodycc)) {
+	foreach my $entry (qw (sob bodycc misc-by)) {
 		$suppress_cc{$entry} = 1;
 	}
 	delete $suppress_cc{'body'};
@@ -1681,7 +1681,7 @@
 	# Now parse the message body
 	while(<$fh>) {
 		$message .=  $_;
-		if (/^(Signed-off-by|Cc): (.*)/i) {
+		if (/^([a-z-]*-by|Cc): (.*)/i) {
 			chomp;
 			my ($what, $c) = ($1, $2);
 			# strip garbage for the address we'll use:
@@ -1691,8 +1691,13 @@
 			if ($sc eq $sender) {
 				next if ($suppress_cc{'self'});
 			} else {
-				next if $suppress_cc{'sob'} and $what =~ /Signed-off-by/i;
-				next if $suppress_cc{'bodycc'} and $what =~ /Cc/i;
+				if ($what =~ /^Signed-off-by$/i) {
+					next if $suppress_cc{'sob'};
+				} elsif ($what =~ /-by$/i) {
+					next if $suppress_cc{'misc-by'};
+				} elsif ($what =~ /Cc/i) {
+					next if $suppress_cc{'bodycc'};
+				}
 			}
 			if ($c !~ /.+@.+|<.+>/) {
 				printf("(body) Ignoring %s from line '%s'\n",