Updating to CloudEvent 1.0 compliant events (#2196)

* Updating to CloudEvent 1.0 compliant events

* implementing suggestions from Nacho

* implementing suggestions from Nacho

docs/eventing/samples/kafka/source/README.md

@@ -77,7 +77,25 @@ You must ensure that you meet the [prerequisites listed in the Apache Kafka over
 
 ### Create the Event Display service
 
-1. Build and deploy the Event Display Service.
+1. Build the Event Display Service (`even-display.yaml`)
+
+   ```yaml
+   apiVersion: serving.knative.dev/v1
+   kind: Service
+   metadata:
+     name: event-display
+     namespace: default
+   spec:
+     template:
+       spec:
+         containers:
+           - # This corresponds to
+             # https://github.com/knative/eventing-contrib/tree/master/cmd/event_display/main.go
+             image: gcr.io/knative-releases/github.com/knative/eventing-contrib/cmd/event_display
+   ```
+
+1. Deploy the Event Display Service
+
    ```
    $ kubectl apply --filename source/samples/event-display.yaml
    ...
@@ -160,12 +178,13 @@ You must ensure that you meet the [prerequisites listed in the Apache Kafka over
   ☁️  cloudevents.Event
   Validation: valid
   Context Attributes,
-      specversion: 0.3
+    specversion: 1.0
     type: dev.knative.kafka.event
-      source: dubee
+    source: /apis/v1/namespaces/default/kafkasources/kafka-source#my-topic
-      id: partition:0/offset:333
+    subject: partition:0#564
-      time: 2019-10-18T15:23:20.809775386Z
+    id: partition:0/offset:564
-      contenttype: application/json
+    time: 2020-02-10T18:10:23.861866615Z
+    datacontenttype: application/json
   Extensions,
     key:
   Data,