Refactor the "os availability zone list" command to make it a common
command instead of a compute-only command. Since availability zones
are common to compute, volume and network (new), this refactoring
allows availability zone support to be added for volume and network.

In addition to the refactor, unit and functional tests were added.

Change-Id: I63e9d41d229b21cd38e5a083493042c096d65e05
Partial-Bug: #1532945

We have a class FakeVolume to fake one or more volumes. So use it in
test_server.py.

Change-Id: I735ae7f678a6799e0ae4c7c25c8083d9ebf47b09
Implements: blueprint improve-volume-unittest-framework

Add a set of testcases to test the classes of
ListService and SetService in the compute.v2.service.
And to be consistent with cinder term, use service_binary
to represent the service binary.

Change-Id: I9fe740f07c9ce3afdba7b7cca152d614170abb96

A validation is necessary to check the existence of project.
This patch is similar to Ia2d8c96527820e25b074e6486d3f39c5ad7eae60.

Change-Id: Id8895ba7a21ecad05942619a82a87c0dc68eae53

The new class FakeFlavor has been introduced to fake one or more flavors.
So use it and remove the old fake flavor data.

Change-Id: Ie3a33b36ae6e597c6a0b1d17ad13c73cf4b73bc9
Implements: blueprint improve-flavor-unit-test

Change-Id: I1b20e7d50e478ce8114ca08aa455b7acad4ea7f5
Implements: blueprint improve-flavor-unit-test

Just like FakeServer and FakeResource, FakeFlavorResource should be in compute_fakes.py.

Change-Id: I8315256fb90377605fa2190e24c9674f6aaf6efd
Implements: blueprint improve-flavor-unit-test

FakeServer should not be in tests.fakes since this should
be just for generic re-usable classes.

Change-Id: I19209952de69626dfa3caadc5d1cc69b7feadeba