objects: introduce numa pages topology as an object

Introduces object NUMAPagesTopology also remove the one
from hardware.py which will be not used.

Work-Item: Enhance libvirt driver to report available
           large pages per NUMA node in the host state data

Change-Id: I004c87c5c5b2b42fda04b5754b77a83fadd44281
Partial-Implement: blueprint virt-driver-large-pages
Merge "objects: introduce numa pages topology as an object"