Pythonified sanity_check.all_tests_passed

Change-Id: I48986344b7af507e2526d4e8bd1b03277f974972
Add comments to iptables rules to help debugging

Adds comments to some of the iptables rules generated
by neutron to assist with debugging.

DocImpact

Partial-Bug: #1265493
Change-Id: I7d9e37b9a43589dd7b142869b86fa15cb3fb329c
Merge "Add comments to iptables rules to help debugging"
Merge "Pythonified sanity_check.all_tests_passed"