chore: import upstream snapshot with attribution

sendmail/edit_mailer.cgi

@@ -0,0 +1,15 @@
+#!/usr/local/bin/perl
+# edit_mailer.cgi
+# Edit an existing mailer
+
+require './sendmail-lib.pl';
+require './mailers-lib.pl';
+&ReadParse();
+$access{'mailers'} || &error($text{'mform_ecannot'});
+$conf = &get_sendmailcf();
+@virts = &list_mailers(&mailers_file($conf));
+
+&ui_print_header(undef, $text{'mform_edit'}, "");
+&mailer_form($virts[$in{'num'}]);
+&ui_print_footer("list_mailers.cgi", $text{'mailers_return'},
+	"", $text{'index_return'});