cleanup lab003-compute-node
cleanup lab003-compute-node

corrected spelling Open vSwitch
added parenthasis
added the before previous section

Change-Id: If09f59e44d087af196d9f8bf4a45b1406ac1c53b

Nabs007/training-guides,harrisonfeng/training-guides,harrisonfeng/training-guides,Nabs007/training-guides,harrisonfeng/training-guides,openstack/training-guides,Nabs007/training-guides,openstack/training-guides