I'm trying to get inbound messages to my e-mail adapter to trigger a dialogue, however I'm not sure where I can access the e-mail header or file attachments, required for my dialogue and the API docs are not clear on this (http://docs.askfast.apiary.io/reference/adapter/adapters). All I get is the inbound e-mail's body POSTed to the follow-up Question's only answer/option in the Answer.answer_text field.