Some small cleanup to docs.

docs/packaging.md

@@ -1,15 +1,18 @@
 # Packaging your Function
 
+## Option 1 (recommended): Use the `fn` cli tool
+
+We recommend using the [fn cli tool](../fn/README.md) which will handle all of this for you. But if you'd like to dig in
+and customize your images, look at Option 2.
+
+## Option 2: Build your own images
+
 Packaging a function has two parts:
 
 * Create a Docker image for your function with an ENTRYPOINT
 * Push your Docker image to a registry (Docker Hub by default)
 
-Once it's pushed to a registry, you can use it by referencing it when adding a route.
-
-## Using fn
-
-This is the easiest way to build, package and deploy your functions.
+Once it's pushed to a registry, you can use the image location when adding a route.
 
 ### Creating an image
 
@@ -17,7 +20,7 @@ The basic Dockerfile for most languages is along these lines:
 
 ```
 # Choose base image
-FROM golang:alpine
+FROM funcy/node:dev
 # Set the working directory
 WORKDIR /function
 # Add your binary or code to the working directory
@@ -26,29 +29,16 @@ ADD funcbin /function/
 ENTRYPOINT ["./funcbin"]
 ```
 
-Then you simply build your function:
+Then build your function image:
 
 ```sh
-docker run --rm -v ${pwd}:/go/src/$FUNCPKG -w /go/src/$FUNCPKG funcy/go:dev go build -o funcbin
 docker build -t $USERNAME/myfunction .
 ```
 
-Or using [fn](../fn/README.md):
-
-```sh
-fn build
-```
-
 ### Push your image
 
-This part is simple:
-
 ```sh
 docker push $USERNAME/myfunction
 ```
 
-Or using [fn](../fn/README.md):
-
-```sh
-fn push
-```
+Now you can use that image when creating or updating routes.