NewMailer creates a new instance of Mailer.

NewSender returns a new Sender instance.

ErrInvalidEmailConfiguration is returned when the email URI given in the environment (ACCOUNTS_EMAIL_URI) is either empty or otherwise invalid.

From is the address we send emails from.

PortalAddressAccounts defines the URI where we can access the accounts sub-site.

ServerLockID holds the name of the name of this particular server.

Mailer prepares messages for sending by adding them to the email queue.