Adds support for the Hyper-V WMI V2 namespace

Blueprint: hyper-v-wmi-v2

The Hyper-V APIs are mainly based on WMI. The original 2008 Hyper-V
release introduced the "root\virtualization" namespace which got
superseded in Hyper-V Server / Windows Server 2012 by the
"root\virtualization\v2" namespace (referred as V2 in the sources).

The original namespace has been dropped in the upcoming Hyper-V 2012
R2 (currently available in preview), which means that the Grizzly code
will not be compatible with it as is.

The Hyper-V driver is structured with a clear decoupling between OS
interaction classes (so called *utils modules and classes) and the
agent's logic.

This allows us to provide an implementation of the V2 API without
impacting the rest of the agent's code, based on a factory module
added to instantiate the proper version of the *utils classes: the
original "V1" ones for versions of the OS predating 2012 and the
newer "V2" ones starting from Hyper-V 2012 (Windows kernel version
6.2).

Change-Id: I380d8c65715242d8a5b94b5061ebe4f30e6c2090
Merge "Adds support for the Hyper-V WMI V2 namespace"