This allows an easy to use cli which invokes the export function to get
the keyring and uses the ownertrust and revoke functions to write all
artifacts into a target directory.
This gives more control over the export command that may be useful to
export a single packager to import it into gpg. This will also give more
flexibility to chain this function to the future verify stage.
By default the command exports the whole keyring directory.
Include a readme with steps how to add/remove/update a key in the
keyring and how to release a new keyring version.
Signed-off-by: Jelle van der Waa <jelle@vdwaa.nl>
