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 multinic extension to v3 API Part 1"