Revert "Deletes floating ip related connection states"

This reverts commit 3a30d19e4e2e5bf4f54045561158661b43beecb3.

The change pulled in a new runtime dependency on conntrack-tools
that was not present in previous Icehouse releases. Leaving the
patch applied in the branch means that all distributions are
either forced to ship the new package and its dependencies in
their repositories, or patch out the fix. Also, running
conntrack in network namespaces can be problematic on some of
platforms with old kernels (like RHEL6).

Change-Id: I0cb896d5bef9982cb862a195ec4010f62bded39c
Merge "Revert "Deletes floating ip related connection states"" into stable/icehouse