Add PodPreset support (openshift#917)

* Add support for PodPreset

* Regen code

contrib/examples/walkthrough/ups-binding-pp.yaml

@@ -0,0 +1,14 @@
+apiVersion: servicecatalog.k8s.io/v1alpha1
+kind: Binding
+metadata:
+  name: ups-binding
+  namespace: test-ns
+spec:
+  instanceRef:
+    name: ups-instance
+  secretName: my-secret
+  alphaPodPresetTemplate:
+    name: my-pod-preset
+    selector:
+      matchLabels:
+        app: my-app

pkg/apis/servicecatalog/types.go

@@ -369,6 +369,28 @@ type BindingSpec struct {
 	//
 	// Immutable.
 	ExternalID string
+
+	// Currently, this field is ALPHA: it may change or disappear at any time
+	// and its data will not be migrated.
+	//
+	// AlphaPodPresetTemplate describes how a PodPreset should be created once
+	// the Binding has been made. If supplied, a PodPreset will be created
+	// using information in this field once the Binding has been made in the
+	// Broker. The PodPreset will use the EnvFrom feature to expose the keys
+	// from the Secret (specified by SecretName) that holds the Binding
+	// information into Pods.
+	//
+	// In the future, we will provide a higher degree of control over the PodPreset.
+	AlphaPodPresetTemplate *AlphaPodPresetTemplate
+}
+
+// AlphaPodPresetTemplate represents how a PodPreset should be created for a
+// Binding.
+type AlphaPodPresetTemplate struct {
+	// Name is the name of the PodPreset to create.
+	Name string
+	// Selector is the LabelSelector of the PodPreset to create.
+	Selector metav1.LabelSelector
 }
 
 // BindingStatus represents the current status of a Binding.