update changelog

CHANGELOG

@@ -7,6 +7,11 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+Make FIDO available
+Fix "remove the reverse-alias" when replying
+Update GET /mailboxes
+Create POST /api/v3/alias/custom/new
+Add PGP for contact
 
 ## [3.1.1] - 2020-05-27
 Fix alias creation

cron.py

@@ -269,7 +269,9 @@ nb_app: {stats_today.nb_app} - {increase_percent(stats_yesterday.nb_app, stats_t
 
 
 def sanity_check():
-    """Different sanity checks
+    """
+    #TODO: investigate why DNS sometimes not working
+    Different sanity checks
     - detect if there's mailbox that's using a invalid domain
     """
     for mailbox in Mailbox.filter_by(verified=True).all():