[WIP] Micro Runtime (#947)

* Add Get() and GetOptions.

* Removed watcher. Outline of client. YAML templates

* Added default service and deployment templates and types

* Added API tests and cleaned up errors.

* Small refactoring. Template package is no more.

* Ripped out existing code in preparation to small rework

* Reshuffled the source code to make it organized better

* Create service and deployment in kubernetes runtime

* Major cleanup and refactoring of Kubernetes runtime

* Service now handles low level K8s API calls across both K8s deployment
an service API objects
* Runtime has a task queue that serves for queueing runtime action
requests
* General refactoring

* No need for Lock in k8s service

* Added kubernetes runtime env var to default deployment

* Enable running different versions of the same service

* Can't delete services through labels

* Proto cruft. Added runtime.CreateOptions implementation in proto

* Removed proxy service from default env variables

* Make service name mandatory param to Get method

* Get Delete changes from https://github.com/micro/go-micro/pull/945

* Replaced template files with global variables

* Validate service names before sending K8s API request

* Refactored Kubernetes API client. Fixed typos.

* Added client.Resource to make API resources more explicit in code

runtime/kubernetes/client/utils_test.go

@@ -0,0 +1,25 @@
+package client
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestTemplates(t *testing.T) {
+	name := "foo"
+	version := "1.2.3"
+
+	// Render default service
+	s := DefaultService(name, version)
+	bs := new(bytes.Buffer)
+	if err := renderTemplate(serviceTmpl, bs, s); err != nil {
+		t.Errorf("Failed to render kubernetes service: %v", err)
+	}
+
+	// Render default deployment
+	d := DefaultDeployment(name, version)
+	bd := new(bytes.Buffer)
+	if err := renderTemplate(deploymentTmpl, bd, d); err != nil {
+		t.Errorf("Failed to render kubernetes deployment: %v", err)
+	}
+}