Introduce a test suite for the nwfilter functionality. Compares
the XML against actual iptables/ebtables rules create. Expects
presence of virbr0 network, and only works with qemu://system
on Linux hosts.
* bin/libvirt-tck: Ensure config file path is absolute
* scripts/nwfilter/100-apply-verify.t: Wrapper to make script
* scripts/nwfilter/nwfilter2vmtest.sh: Main test script
scripts/nwfilter/nwfilterxml2xmlin/*: Test data files