Adds a cli based tool to add/update/replace qdiscs. This tool requires
each qdisc to be supported via a dynamic loadable module in
pkglibdir/cli/qdisc/$name.so.
So far HTB and blackhole have been implemented.
Syntax:
nl-qdisc-add --dev eth2 --parent root --id 1: htb --r2q=5
nl-qdisc-add --update-only --dev eth2 --id 1: htb --r2q=10