Apic drivers enhancements (second approach): L2 refactor

- refactor to leverage Client's transactional capabilities
- General refactor to improve the driver's reliability

Implements blueprint: apic-driver-enhancements

Change-Id: I4deb171381e62e70818218957d82b5e27954aeb9
Provide a quick way to run flake8

"run_tests.sh -p" always checks every file for errors even though you
have probably only changed a handful. This patch adds "run_tests.sh -8"
which only checks the files that were modified in the HEAD commit or
in the current working tree.

It is borrowed from the recent nova commit b011325cc6.
The related ML post is:
http://lists.openstack.org/pipermail/openstack-dev/2014-August/043346.html

Change-Id: Ieeabf1b79a0790af8bde3144dca59b4245a0b79a
Merge "Fix IpNetnsCommand to execute without root_wrapper when no netns"
Merge "Add functional test for l3_agent"
Merge "Fix state_path in tests"
Merge "Block downgrade from icehouse to havana"
Merge "Remove ovs dependency in embrane plugin"
Merge "NSX: log request body to NSX as debug"
Merge "remove explicit include of the ovs plugin"
Merge "Inline "for val in [ref]" statements"
Improve some plugins help strings

For consistency add a "." everywhere, remove an extra space at end of a
string, add missing space between strings, fix descriptions and
capitalization.

Change-Id: Ib1523352b19768425263c09855d6a218e06e588a
Merge "Apic drivers enhancements (second approach): L2 refactor"
Merge "Adding mechanism driver in ML2 plugin for Nuage Networks"
Merge "Make SecurityGroupsRpcCallback a separate callback class"
Cisco DFA ML2 Mechanism Driver

Part 1:
This commit contains changes to support ML2 mechanism driver for Cisco
DFA. For more details please see the blueprint which has more description and
link to document with requirements.

Part 2: Changes in OVS neutron agent.
(http://review.openstack.org/110065)

Part 3: DFA extension driver.
(http://review.openstack.org/111761)

Part 4: DFA config profile service plugin.
(http://review.openstack.org/111863)

Change-Id: Ib53b6705948e1ed75059b85d8809562d9bb63f65
Partially Implements: blueprint ml2-mechanism-driver-for-cisco-dfa
Support for extensions in ML2

The current ML2 plugin supports only extensions defined in the plugin and it
does not support any extensions in the mechanism drivers. The changes in this
commit allows mechanism drivers to define new extensions.

Change-Id: I28da19fabf6de2e9f0d687f875aaaa24c8bbc4f0
Implements: blueprint extensions-in-ml2
Merge "Datacenter moid should not be tuple"
Merge "metering driver default value is different in code and config file"
Introduces a keepalived manager for HA

This patch introduces a keepalived manager
which will be used for the blueprint
blueprint l3-high-availability.

The manager can create a keepalived.conf compliant configuration,
start, stop and restart the service, as well as create keepalived
notification scripts.

Implements: blueprint l3-high-availability
Change-Id: I1ba9f332778f27de950d9e97d4fb4a337f6f26da
Co-Authored-By: Assaf Muller <amuller@redhat.com>
Merge "Cisco DFA ML2 Mechanism Driver"