Add unit tests for Open vSwitch Quantum plugin

OVSQuantumAgent missed unit tests for tunneling
functionality. This change add these tests and couple
of other minor tests.

Implements: blueprint quantum-unittests

Change-Id: I809711de8292ff7610b3fdb496c6bd043e7b6031
Allow nicira plugin to handle multiple NVP API versions

Bug #1126352

This patch introduces a simple framework for enabling
nvlib to call the appropriate routine according to the
current version. To this aim, we leverage the 'server' header
which is returned by every NVP API calls (except login/logout).
The patch also accounts for the changes introduced in NVP 3.0

Change-Id: Ief3a6f2b5b99ea33548353ce3bee3fa23e42752f
Update nvplib to use HTTP constants

Change-Id: I5afe0796de2387566705d6669834d6bfac87ee8d
Unable to update port as non-admin nvp plugin

The port security patch to the nvp plugin broken the ability to update a port
as a non admin user. This patch fixes that and adds a unit test for updating
a port as a non-admin user since there was not one before.

Fixes bug 1127514

Change-Id: I9ac44a8eef14e5beeee020a901615e067ed50fbe
Imported Translations from Transifex

Change-Id: I64b95ea422402e01c25521dc72817bd9ca8c1491
Merge "Add unit tests for Open vSwitch Quantum plugin"
Merge "Imported Translations from Transifex"
Merge "Unable to update port as non-admin nvp plugin"
Merge "Allow nicira plugin to handle multiple NVP API versions"