Add multiqueue support

Add multiqueue support

Problem:
Neither OVS nor SRIOV multi-queue is not supported. Guest VM lacks tuning to reach high throughput.
Solution:
(1) Build SRIOV multi-queue capable guest image by recompiling the igxbevf driver (make CFLAGS_EXTRA=-DIXGBE_ENABLE_VF_MQ install).
(2) Change pktgen to send on multiple queues.
(3) Add tuning in guest VM (Disable irqbalance and setup vNIC interrupt affinity to vCPUs)

Update 1: Takes care comments plus adds unit test cases
Update 2: Jenkins reports code coverage 81%, local reports 96%, add more unit test cases
Update 3: Manually rebased to adapt to SSH.from_node()
Update 4: Takes care comments for vnic_type, vnic_name

Change-Id: Ieb15381c653b13697487d095efa4be6c3c49fa42
JIRA: YARDSTICK-619
Signed-off-by: Jing Zhang <jing.c.zhang@nokia.com>