[WIP] K8s update and runtime package changes (#895)

* First commit: outline of K8s runtime package

* Added poller. Added auto-updater into default runtime

* Added build and updated Poller interface

* Added comments and NewRuntime that accepts Options

* DefaultPoller; Runtime options

* First commit to add Kubernetes cruft

* Add comments

* Add micro- prefix to K8s runtime service names

* Get rid of import cycles. Move K8s runtime into main runtime package

* Major refactoring: Poller replaced by Notifier

POller has been replaced by Notifier which returns a channel of events
that can be consumed and acted upon.

* Added runtime configuration options

* K8s runtime is now Kubernetes runtime in dedicated pkg. Naming kung-fu.

* Fix typo in command.

* Fixed typo

* Dont Delete service when runtime stops.

runtime.Stop stops services; no need to double-stop

* Track runtime services

* Parse Unix timestamps properly

* Added deployments into K8s client. Debug logging

config/cmd/options.go

@@ -7,6 +7,7 @@ import (
 	"github.com/micro/go-micro/client"
 	"github.com/micro/go-micro/client/selector"
 	"github.com/micro/go-micro/registry"
+	"github.com/micro/go-micro/runtime"
 	"github.com/micro/go-micro/server"
 	"github.com/micro/go-micro/transport"
 )
@@ -24,6 +25,7 @@ type Options struct {
 	Transport *transport.Transport
 	Client    *client.Client
 	Server    *server.Server
+	Runtime   *runtime.Runtime
 
 	Brokers    map[string]func(...broker.Option) broker.Broker
 	Clients    map[string]func(...client.Option) client.Client
@@ -31,6 +33,7 @@ type Options struct {
 	Selectors  map[string]func(...selector.Option) selector.Selector
 	Servers    map[string]func(...server.Option) server.Server
 	Transports map[string]func(...transport.Option) transport.Transport
+	Runtimes   map[string]func(...runtime.Option) runtime.Runtime
 
 	// Other options for implementations of the interface
 	// can be stored in a context
@@ -135,3 +138,10 @@ func NewTransport(name string, t func(...transport.Option) transport.Transport)
 		o.Transports[name] = t
 	}
 }
+
+// New runtime func
+func NewRuntime(name string, r func(...runtime.Option) runtime.Runtime) Option {
+	return func(o *Options) {
+		o.Runtimes[name] = r
+	}
+}