Set proper serialization tag.
Make the per-spec test easier to follow.
Keep the serialized name in sync with the field name.
Drop a superfluous empty line.
Drop an unnecessary check in a test.
Add a test for an empty availability zone.
Add a note about why we use bson.M.
Clarify a doc comment.
gc.DeepEquals -> jc.DeepEquals.
provcommon -> common.
Add the API entry point for entity zones.
Add a test for InstanceId.
Add a test for Zone in the API server.
Add a test for Zone in the API client.
Prep unit-get for more settings.
Add "zone" to unit-get.
Add the Zone method to Context, using the API end-point.
Zone -> AvailabilityZone.
In-line an error test.
Use errors.