Give access to Avahi to resolve the .local mDNS domain
    
    The nss-mdns plugin for the GNU Name Service Switch (or NSS)
    functionality of the GNU C Library is necessary to resolve the .local
    mDNS domain. The plugin talks to the Avahi daemon running on the host
    to resolve the names.
    
    https://github.com/containers/toolbox/issues/209