Accept incoming mail on devserver role
On FreeBSD, by default, sendmail is configured to only send mail, not receive:
sendmail_enable="NO" # Run the sendmail inbound daemon (YES/NO).
To get a simple incoming working configuration, to enable the inbound daemon is enough.
Test Plan: Send mails from nc, see T1317 last comments.
Reviewed By: dereckson
Maniphest Tasks: T1317
Differential Revision: https://devcentral.nasqueron.org/D1976