This commit just fixes things to the point where pusher updates are
applied to the store properly. This still lacks a business logic fixes,
so for example we won't update lastBuild's field, because there's no
such information from pusher.
* we should look for both embedded relationship and relationship key,
so in cases like for commit, when there's a full commit data on
"commit" property, and only id at "commit_id", we will use commit data
* we can't add @type to V2 fallback, because in other places we chack
for @type to distinguish V2 and V3 payloads
* there's no need to include a record in "included" if there's only a
type and an id there
For some reason (probably some problem with one of the serializers) we
sometimes lack an id attribute for a promise that we get for a repo
relationship on build. Because of that doing `build.get('repo.id')` may
sometimes return undefined. A temporary workaround is to make sure that
we always can access the `repository_id` property.
Since we change repos property on reposController, we can't set observer
on repos, because as soon as it's changed, we loose the observer.
Instead, we should observe only on reposController, which is not going
to change.
One thing that is not standard here is a serializer for branch, which
uses @href as id. At this point branches don't have ids and ember-data
needs one, so using @href is the easiest way.
This commit adds adapters and serializers for v3, but also a fallback
serializer for v2, which allows to handle v2 and v3 payloads at the same
time. This is needed, because when we use v3 endpoint for one of the
models (in this case repo), we can also get embedded records of other
types (like branch or build).
