port AvailabilityZone API into v3 part1

This changeset only copies the v2 files into the appropriate v3
directories 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 tried 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.

Partially implements: bp v3-api-extension-versioning

Change-Id: I88f81d76a8dd0559e5a64a3c9d8aa93c6d2fa107
Port AvailabilityZone API to v3 Part 2

This patch contains the changes required to adapt the AvailabilityZone
extension and the corresponding unittest to the v3 framework. Moves the
commented out tests from the v3 version of test_servers to the config
drive extension unittests.

Partially implements: bp v3-api-extension-versioning

Change-Id: I2cf214061e3accbb056ca53c224df1c5bf74a6e4
Merge "port AvailabilityZone API into v3 part1"
Merge "Port AvailabilityZone API to v3 Part 2"
Merge remote-tracking branch 'm_src_repo/citrix-fixes' into build-temp