Add basic support for email attachments.

This is hopefully at least somewhat proper...

rattail/mail.py

@@ -31,6 +31,8 @@ import smtplib
 import warnings
 import logging
 from email.message import Message
+from email.mime.multipart import MIMEMultipart
+from email.mime.text import MIMEText
 
 from mako.lookup import TemplateLookup
 
@@ -196,8 +198,16 @@ def make_message_config(config, key, body, subject=None, recipients=None, attach
        foo.bcc =
            admin@example.com
     """
-    message = Message()
-    message.set_type('text/html')
+    if attachments is not None:
+        message = MIMEMultipart()
+        message.attach(MIMEText(body))
+        for attachment in attachments:
+            message.attach(attachment)
+    else:
+        message = Message()
+        message.set_payload(body, 'utf_8')
+        message.set_type('text/html')
+
     message['From'] = get_sender(config, key)
     if recipients is None:
         recipients = get_recipients(config, key)
@@ -206,7 +216,6 @@ def make_message_config(config, key, body, subject=None, recipients=None, attach
     if subject is None:
         subject = get_subject(config, key)
     message['Subject'] = subject
-    message.set_payload(body, 'utf_8')
     return message