Support separate mailer address and instance admin address
At the moment, Pleroma only has one instance-wide E-mail address configured using config :pleroma, :instance, email
, which is used both for contact information, and for sending E-mails.
This means that it is for example not possible to list admin@example.com
in places such as the /api/v1/instance
endpoint, while using noreply@example.com
to send automated E-mails.
Contact info and sent E-mails should be able to use different addresses.