[interchange] Teach send_mail() about MV_EMAIL_CHARSET

[David Christensen]

commit ed509da0b64bf62988c48d88cc62bad1a4c7ec41
Author: David Christensen <david at endpoint.com>
Date:   Mon Aug 13 16:38:59 2018 -0500

    Teach send_mail() about MV_EMAIL_CHARSET

 lib/Vend/Util.pm |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)
---
diff --git a/lib/Vend/Util.pm b/lib/Vend/Util.pm
index 5e2c82c..0a17335 100644
--- a/lib/Vend/Util.pm
+++ b/lib/Vend/Util.pm
@@ -2124,6 +2124,12 @@ sub cookies_hash {
 sub send_mail {
 	my($to, $subject, $body, $reply, $use_mime, @extra_headers) = @_;
 
+	if (my $charset = $::Variable->{MV_EMAIL_CHARSET} || $Global::Variable->{MV_EMAIL_CHARSET}) {
+		if (!grep /content-type/i, @extra_headers) {
+			push @extra_headers, "Content-type: text/plain; charset=$charset";
+		}
+	}
+
 	if(ref $to) {
 		my $head = $to;