[j-nsp] instance-specific filters for VPLS BUM/flood filtering

[Per Granath]

http://www.juniper.net/techpubs/en_US/junos11.4/topics/usage-guidelines/vpns-configuring-firewall-filters-and-policers-for-vpls.html

[edit routing-instances routing-instance-name forwarding-options family vpls]
filter input input-filter-name;

> is there a knob so that I can get instance-specific forwarding filters for the
> BUM/flood filter option in VPLS instances? I want to define one filter and
> apply it via apply-group but I need to generate separate filters for every
> instance it is applied to.