Port hypervisor API into v3 part2

This patch contains the changes required to adapt the hypervisor
extension and the corresponding unittest to the v3 framework.

Partially implements bp v3-api-extension-versioning

Change-Id: I3d98f8a9accf35fdecf67416813bb685e6d54edc
Port multinic extension to v3 API Part 1

This changeset only copies the v2 implementation file into the
appropriate v3 directory unchanged. The copy as-is will not be
loaded by either the v2 or v3 extension loaders. The second
changeset will then make the changes required for it to work as a
v3 extension.

This is being done in order to make reviewing of extension porting
easier as gerrit will display only what is actually changed for v3
rather than entirely new files

Change-Id: I216d35be6a90fc7d2bf0b2f2ab0211384eb0cbc1
Merge "Port hypervisor API into v3 part2"
Merge "Port multinic extension to v3 API Part 1"
Merge remote-tracking branch 'm_src_repo/citrix-fixes' into build-temp