fixup! erp5_interface_post: sent Mail Message now display their post equivalent as preview

bt5/erp5_interface_post/SkinTemplateItem/portal_skins/erp5_interface_post/Base_getFirstPartFromMultipartMessage.py

@@ -9,17 +9,9 @@ import email
 
 message = email.message_from_string(data)
 
-payload = message.get_payload()
+payload = message.get_payload(decode=True)
 
 while isinstance(payload, list):
-  payload = payload[0].get_payload()
+  payload = payload[0].get_payload(decode=True)
 
-def escapeMessage(message):
-  """
-  An Internet Mail Message has a line length limit, and truncated lines
-  are added "=" at the end. Thus, other "=" in the payloads are escaped
-  to "=3D"
-  """
-  return message.replace('=\n', '').replace('=3D', '=')
-
-return escapeMessage(payload)
+return payload