Forwarding emails into Discourse without staging users

[LeoMcA (Leo McArdle)]

I think that’s what I advocate here:

`enable_forwarded_emails` doesn't behave like conventional email forwarding

enable_forwarded_emails is a great feature for bringing existing conversations into Discourse, but for users who approach Discourse with a “Mailman-mind” - as many users on our instance do - this feature just doesn’t do what they’re expecting it to. Within every email client I’ve used, forwarding an email intentionally excludes the original email address from the forward, and subsequent replies. Whereas with this feature, that original email address is included in the created post and subsequen…

I haven’t started working on a PR, I’ve got a few other priorities at the moment.