add vendoring

vendor/github.com/jhillyerd/enmime/sender.go

@@ -0,0 +1,33 @@
+package enmime
+
+import "net/smtp"
+
+// Sender provides a method for enmime to send an email.
+type Sender interface {
+	// Sends the provided msg to the specified recipients, providing the specified reverse-path to
+	// the mail server to use for delivery error reporting.
+	//
+	// The message headers should usually include fields such as "From", "To", "Subject", and "Cc".
+	// Sending "Bcc" messages is accomplished by including an email address in the recipients
+	// parameter but not including it in the message headers.
+	Send(reversePath string, recipients []string, msg []byte) error
+}
+
+// SMTPSender is a Sender backed by Go's built-in net/smtp.SendMail function.
+type SMTPSender struct {
+	addr string
+	auth smtp.Auth
+}
+
+var _ Sender = &SMTPSender{}
+
+// NewSMTP creates a new SMTPSender, which uses net/smtp.SendMail, and accepts the same
+// authentication parameters.  If no authentication is required, `auth` may be nil.
+func NewSMTP(addr string, auth smtp.Auth) *SMTPSender {
+	return &SMTPSender{addr, auth}
+}
+
+// Send a message using net/smtp.SendMail.
+func (s *SMTPSender) Send(reversePath string, recipients []string, msg []byte) error {
+	return smtp.SendMail(s.addr, s.auth, reversePath, recipients, msg)
+}