this commit adds support for the `::add-mask::` command, which was
implemented as a stub before.
it does not cover debug output that appears when you run act in
verbose mode
Co-authored-by: Björn Brauer <bjoern.brauer@new-work.se>
Co-authored-by: Markus Wolf <markus.wolf@new-work.se>
Co-authored-by: Björn Brauer <bjoern.brauer@new-work.se>
Co-authored-by: Markus Wolf <markus.wolf@new-work.se>