Add kubernetes podSpec support in fission spec (#1106)

pkg/apis/fission.io/v1/typefields.go

@@ -223,6 +223,16 @@ type (
 		// - ImagePullPolicy
 		// (optional)
 		Container *apiv1.Container `json:"container,omitempty"`
+
+		// Podspec allows modification of deployed runtime pod with Kubernetes PodSpec
+		// The merging logic is briefly described below and detailed MergePodSpec function
+		// - Volumes mounts and env variables for function and fetcher container are appended
+		// - All additional containers and init containers are appended
+		// - Volume definitions are appended
+		// - Lists such as tolerations, ImagePullSecrets, HostAliases are appended
+		// - Structs are merged and variables from pod spec take precedence
+		// (optional)
+		PodSpec *apiv1.PodSpec `json:"podspec,omitempty"`
 	}
 
 	Builder struct {