Filtering links not containing a given tag

[ajmas]

Summary

We would like to be able to filter short-link that do no include a given tag. This could either be via a negation character -tag or a new argument.

Use case

The app we are implementing provides a layer of access control around shlink functionality and entry listing, and we would like to hide certain short-links from a certain category of users. To indicate these short-links should be hidden, we add a hidden tag (though it could be anything). Using this we would like to filter out the entries on the shlink side.

For now we are doing this on the side of our app, but it does throw off the match count.