Fix Cisco Nexus plugin failures for vlan IDs 1006-4094

Fixes bug 1174593

VLAN IDs in the range 1006-4094 are considered to be in the extended
range by the Cisco Nexus 3K switch. As such, the 3K rejects any
state change configuration commands for VLANs in this range, including
"state active" and "no shutdown". The errors returned by the 3K for
these commands can be ignored, since the default states for these commands
are acceptable for the 3K.

For the 5K and 7K versions of the Nexus switch, on the other hand, the
"state active" and "no shutdown" commands are required for proper VLAN
configuration, regardless of VLAN ID.

This fix splits the configuration commands which are used to create a
VLAN on the Nexus switch into three separate configurations:
  - VLAN creation
  - state active
  - no shutdown
For the "state active" and "no shutdown" configurations, the Cisco Nexus
plugin will tolerate (ignore) errors involving invalid setting of state
for VLANs in the extended VLAN range. These specific errors can be
identified by looking for the appearance of certain signature strings
in the associated exception's message string, i.e. "Can't modify
state for extended" or "Command is allowed on VLAN".

This approach will yield a very small hit in performance, but the solution
is much less error prone than requiring customers to configure the
Cisco plugin for 3K vs. 5K vs. 7K, or perhaps even specific software
versions of the 3K, in order to inform the Cisco plugin whether
VLAN state configuration commands should be used or not.

Change-Id: I1be4966ddc6f462bca38428c4f904f8c982f318f
Add update method of security group name and description

make it possible to edit the name and description of
common security groups, we can not rename the default
security group.

Fixes: bug #918393

Change-Id: I7003c47e054f032572adbb901be4dbc61839b695
Enable network to be scheduled to N DHCP agents

Fixes bug 1174132

Change-Id: Iabe96fd8a98f3539eb21268fb5ef58df8dbd8782
Merge "Add update method of security group name and description"
Reference OVS OptGoup names in lowercase

To have consistent option group name format across projects,
oslo.config now normalizes all non lowercase group names to lowercase
when loading conf files.
Thus conf files are backwards compatible but option group references
in the code must now use lowercase before we update oslo.config.

This patch replaces all 'OVS' references to 'ovs'

Change-Id: Id8697138d822e331a6776f847915c61b40f8dd6a
Recycle IPs used by 'gateway' ports

Bug 1182602

Previous code simply removed IP allocation for these ports which
should never have an IP. This patch triggers IP recycling so the
IP addresses can be reused by other ports.

Change-Id: I594e02d5bbc78b219eab07e595cde713d6450ffe
Restore correct alias for network-gateway extension

Bug 1182682

Change-Id: I85a93e6ccac32515c7ebb2dfe41ba67cf11c9d9f
Merge "Enable network to be scheduled to N DHCP agents"
Merge "Restore correct alias for network-gateway extension"
Revert "Fix ./run_tests.sh --pep8"

We are explicitly trying to get rid of scripts like this and flake8 makes
this one non-necessary.
Fix run_tests.sh to run flake8 properly.

This reverts commit 42243d6eb221d52bf6f62f835726cbe026e43447

Change-Id: I435e34b6acde7931a75f456ccc88da6476581643
Merge "Fix Cisco Nexus plugin failures for vlan IDs 1006-4094"
reference quota options in lowercase

QUOTAS section have been renamed to quotas so reference quota options in
lowercase.

fixes bug 1182772

Change-Id: Ia08cb51deacc26620e512020b6a3c3b67185ec34
Merge "Revert "Fix ./run_tests.sh --pep8""
Merge "Recycle IPs used by 'gateway' ports"