update helloworld example (#550)

Signed-off-by: Matthew Fisher <matt.fisher@microsoft.com>

README.md

@@ -41,25 +41,49 @@ Duffle is a command line tool that allows you to install and manage CNAB bundles
 
     ```console
     $ duffle build ./examples/helloworld/
-    Duffle Build Started: 'helloworld': 01CS02FNS3FTM9907V83GAQQMT
-    helloworld: Building CNAB components: SUCCESS ⚓  (1.0090s)
+    Step 1/5 : FROM alpine:latest
+    ---> 196d12cf6ab1
+    Step 2/5 : RUN apk add -u bash
+    ---> Using cache
+    ---> 54b3a85c5c2e
+    Step 3/5 : COPY Dockerfile /cnab/Dockerfile
+    ---> Using cache
+    ---> cd6f4ff8d83d
+    Step 4/5 : COPY app /cnab/app
+    ---> 38a482447ffd
+    Step 5/5 : CMD ["/cnab/app/run"]
+    ---> Running in 8b22055f0a37
+    ---> e5c795c2a1f4
+    Successfully built e5c795c2a1f4
+    Successfully tagged deislabs/helloworld-cnab:64dfc7c4d825fe87506dbaba6ab038eafe2a486d
+    ==> Successfully built bundle helloworld:0.1.0
 
-    $ duffle credentials generate helloworld-creds -f examples/helloworld/cnab/bundle.json
-    name: helloworld-creds
-    credentials:
-    - name: quux
-      source:
-        value: EMPTY
-      destination:
-        path: pquux
+6. Check that it was built:
+    ```console
+    $ duffle bundle list
+    NAME            VERSION DIGEST                                          SIGNED?
+    helloworld      0.1.0   b2747e5c36369f4c102f4f879caa94e607e5db7e        true
+    ```
 
-    $ duffle install helloworld-demo -c helloworld-creds -f examples/helloworld/cnab/bundle.json
+7. Now run it:
+    ```console
+    $ duffle credentials generate helloworld-creds helloworld:0.1.0
+    $ duffle install helloworld-demo -c helloworld-creds helloworld:0.1.0
     Executing install action...
-
+    hello world
     Install action
     Action install complete for helloworld-demo
     ```
 
+8. Clean up:
+    ```console
+    $ duffle uninstall helloworld-demo
+    Executing uninstall action...
+    hello world
+    uninstall action
+    Action uninstall complete for helloworld-demo
+    ```
+
     *Notes:*
     * Learn more about what a bundle is and its components [here](https://github.com/deislabs/cnab-spec/blob/master/100-CNAB.md).
     * Get a feel for what CNAB bundles look like by referencing the [bundles repo](https://github.com/deislabs/bundles) on github.

examples/helloworld/cnab/Dockerfile

@@ -1,7 +1,8 @@
 FROM alpine:latest
 
-COPY app/run /cnab/app/run
-COPY bundle.json /cnab/bundle.json
-COPY Dockerfile cnab/Dockerfile
+RUN apk add -u bash
 
-CMD [ "/cnab/app/run" ]
+COPY Dockerfile /cnab/Dockerfile
+COPY app /cnab/app
+
+CMD ["/cnab/app/run"]

examples/helloworld/duffle.json

@@ -0,0 +1,33 @@
+{
+    "name": "helloworld",
+    "version": "0.1.0",
+    "description": "A short description of your bundle",
+    "keywords": [
+        "helloworld",
+        "cnab",
+        "tutorial"
+    ],
+    "maintainers": [
+        {
+            "name": "John Doe",
+            "email": "john.doe@example.com",
+            "url": "https://example.com"
+        },
+        {
+            "name": "Jane Doe",
+            "email": "jane.doe@example.com",
+            "url": "https://example.com"
+        }
+    ],
+    "components": {
+        "cnab": {
+            "name": "cnab",
+            "builder": "docker",
+            "configuration": {
+                "registry": "deislabs"
+            }
+        }
+    },
+    "parameters": null,
+    "credentials": null
+}