Upgrade to wallabag 2.2.1

Easy upgrade of Docker container to new minor version.
But big issues with the following database migration:
[root@ozone wallabag]# docker exec -t bierochs-wallabag /var/www/wallabag/bin/console doctrine:migrations:execute 20161118134328 --down --env=prod --no-interaction -- reverting 20161118134328 SS skipped (Reason: It seems that you already played this migration.) [root@ozone wallabag]# docker exec -t bierochs-wallabag /var/www/wallabag/bin/console doctrine:migrations:execute 20161118134328 --up --env=prod --no-interaction ++ migrating 20161118134328 -> ALTER TABLE wallabag_entry ADD COLUMN http_status VARCHAR(3) DEFAULT NULL ++ migrated (0.13s)
wallabag 2.2.1 release notes