No way to determine message type in message_received handler

[ianp]

For example, when a Facebook bot receives a post back it will trigger both the facebook_postback and message_received events, while this is good for conversational usage it means that messages will be processed twice in some cases. It would be good if there were an easy way to tell if a message had been generated from a post back in the message_received handler.

I'd like to add a type field to the message which would be set to facebook_postback (similar to how the Slack bot adds a type field to some messages).

(Botkit versions 0.4.0 and HEAD)

[agamrafaeli]

Submitted PR #469 to resolve this

[benbrown]

Merged! Thank you!