Implement grpc-gateway in front of the gRPC based sdk-server, so that
it can be access via HTTP+JSON.

This includes documentation and a swagger/openapi specificiation.

This also has been implemented such that the sdk-server is still a single
binary, and as such, the HTTP+JSON interface can still be used for local
development.

Closes #240

This also includes a change on the domain to agones.dev,
and changing the name of the hosting project
infrastructure.

This includes updates to the SDK, and
controller code to manage the health
lifecycle of a GameServer.

Examples have also been updated, as well
as some basic documentation.

Closes #15

First implementation was done in Go as prototyping.
Implementation is done with gRPC so it should be
relatively trivial to generate new SDKs for each
language.

Implemented gRPC sidecars server to accompany the SDK
and processing of the change in states, such that the
IP and Port of the GameServer is available in the
GameServer status when its status is Ready.

Closes #16

Better to be gameserver > controllers, and then gameservers > sidecar
than break out by functionality. More idiomatic go, and easier to
work with.

This implementation just builds the basic foundation of the controller
for this Custom Resource Definition. It will check and see if the
CRD has been defined, and it not, create it in the Kubernetes cluster
it resides in, and wait until it reached an Established state.

Then it just blocks until it gets told to terminate via a process signal.

This includes vendoring for the kubernetes controller framework, crd extensions,
our logging and error management etc.