Modified IPtablesManager.apply() method to save/restore chain and
rule packet:byte counts by using the '-c' flag with iptables-save
and iptables-restore calls. Currently they are zeroed every time
we change something in the table. This will allow users to better
analyze usage for instances over an extended period of time, for
example, for billing purposes.
Change all applicable iptables, libvirt and Xen tests to account
for the changes made to support the packet:byte counts.
This work uncovered two bugs in the existing implementation
found during my testing, specifically:
1. Fix IptablesManager to clean-up non-wrapped chains correctly,
instead of leaving them in the kernel's table. We now keep a
list of chains and rules we need to remove, and double-check
in apply() that they are filtered-out.
2. Fix IptablesManager to honor "top=True" iptables rules by only
adding non-top rules after we've gone through all the top rules
first.
Implements first work item of blueprint libvirt-network-usage.
Fixes bug 1037127 and bug 1037137.
Change-Id: Ia5a11aabbfb45b6c16c8d94757eeaa2041785b60
b71b88502b