feature: add attachments to parse_msg()

[greenpau]

Currently, the Mml()'s parse_msg() function does not include references to attachments.

It would be great to have an indication as to whether a message has attachments, e.g.:

    def parse_msg(self, datafeed):
        for message in datafeed:

... omitted ...
            if 'attachments' in message:
                message_broke['attachments'] = []
                for attachment in message['attachments']:
                    if 'id' in attachment:
                        message_broke['attachments'].append(attachment['id']);
            message_parsed.append(message_broke)

[openfly]

Ugh... yeah also presentation ML is now a thing... this is one of those areas I could really use help on.

[greenpau]

presentation ML

@openfly , it was my interest area 4 years :-) see here

[openfly]

Well if you want to contribute a better approach to parsing this stuff than beautiful soup and triggers... I'd be down.