feat: config option to only send items after initial feed add

[marcaurele]

What

Added a new configuration option only-new so that when a new feed is discovered in the configuration, it will send or not the first run of the items found in the feeds.

Why

When using the tool in a docker image, and as a container batch job on a scheduler like Hashicorp Nomad, all new entries are only added through the configuration file. Therefore the option --only-new is not an option and it should be set through the configuration.

The idea is that when set to True, only items found in the feed after the initial add/run of the new entry will be emailed.

[auouymous]

Why is it you can use the run command but not the add command?

[marcaurele]

Why is it you can use the run command but not the add command?

I schedule the run command as a batch definition in Nomad, which has a schedule at specific time of the day. There is no easy way to run a unique special command in that case. I do not have access to the file system either, the config is defined in batch definition of the job.

I run it on a container orchestrator, not as a crontab on a server.