Only checks authenticated registries for new versions. But if you are using
this you probably aren't using DockerHub anyway.
FAQ
How does Fresh remember the last seen hash? The container hashes are stored
in the same directory as the docker-compose.yml file in a file named fresh.yml.
Remove this file to force trigger an update.
What are these hashes? Fresh grabs the manifest for the image from the registry
and proceeds to hash a concatenation of all the various build layer hashes. This
should mean if the image is new but the layers are the same nothing will be updated.
How do I notify a Mattermost webhook? Mattermost webhooks are compatible with
Slack webhooks, so simply use the --slack flag.