arc/cli/actions/host.py: fix missing import

Signed-off-by: Cleber Rosa <crosa@redhat.com>
man/manpage-writer: add new commands for auto inspection of options

Signed-off-by: Cleber Rosa <crosa@redhat.com>
man page: add missing commands in intro text

Signed-off-by: Cleber Rosa <crosa@redhat.com>