Temporary changes for pre-release

When both pack & lifecycle are released and the samples are updated, we can revert this commit

Signed-off-by: Natalie Arellano <[email protected]>

Author: Natalie Arellano

content/docs/extension-author-guide/create-extension/setup-local-environment.md

@@ -54,6 +54,9 @@ pack version
 
 The version should be at least `0.28.0`
 
+**Note**: to follow this demo all the way through to the end (including run image extension),
+the pack version should be at least `0.30.0-pre2`. Consult the [releases page](https://github.com/buildpacks/pack/releases) for more information.
+
 ### Update pack configuration
 
 <!-- test:exec -->
@@ -70,6 +73,7 @@ We unset any custom lifecycle image that may have been provided to ensure that t
 <!-- test:exec -->
 ```bash
 git clone https://github.com/buildpacks/samples.git
+git checkout runext/update-samples # FIXME: remove when https://github.com/buildpacks/samples/pull/149 is merged
 ```
 
 <!--+ if false +-->

content/docs/extension-author-guide/create-extension/why-dockerfiles.md

@@ -43,6 +43,15 @@ docker run -d --rm -p 5000:5000 registry:2
 You can push the builder to any registry of your choice - just ensure that `docker login` succeeds and replace `localhost:5000` in the following examples with your registry namespace -
 e.g., `index.docker.io/<username>`.
 
+**Note**: to follow this demo all the way through to the end (including run image extension), you will need a pre-release version of the lifecycle.
+* Download the `.tgz` file for your os/arch from the [releases page](https://github.com/buildpacks/lifecycle/releases)
+* Add the following lines to `$PWD/samples/builders/alpine/builder.toml`:
+
+```bash
+[lifecycle]
+uri = <path to .tgz>
+```
+
 Create the builder:
 
 <!-- test:exec -->