Exclusion of kinds/resources/labels

[michaelsauter]

Sometimes, you want Tailor to manage a whole namespace except certain kinds/resources/labels. Currently, this is not possible. We could add a (repeatable) --exclude param, which allows to exclude kinds (e.g. --exclude secret), resources (e.g. --exclude dc/foo) or specific labels (e.g. --exclude foo=bar).

While Tailor should promote the idea of managing everything via Tailor, there are contexts where this is not possible, and if Tailor does not have an --exclude flag, it cannot be used at all ...

[michaelsauter]

This will make it easier to finish opendevstack/ods-jenkins-shared-library#96, and we can use the --exclude flag to distinguish between build-related resources and run-related resources.