now with consume extension notes

Signed-off-by: Joe Kimmel <jkimmel@vmware.com>

content/docs/extension-guide/_index.md

@@ -1,5 +1,5 @@
 +++
-title="Extension Author Guide"
+title="Extension Guide"
 weight=4
 include_summaries=true
 expand=true

content/docs/extension-guide/consume-extension/_index.md

@@ -0,0 +1,32 @@
++++
+title="Consume an extension"
+weight=4
+summary="A few notes to help you consume extensions"
+aliases = [
+  "/docs/extension-author-guide/create-extension"
+  ]
++++
+
+<!--+if false+-->
+## Prerequisites
+
+Before we get started, make sure you've got the following installed:
+
+{{< download-button href="https://store.docker.com/search?type=edition&offering=community" color="blue" >}} Install Docker {{</>}}
+{{< download-button href="/docs/install-pack" color="pink" >}} Install pack {{</>}}
+
+You may also need to [create an extension](/docs/extension-guide/create-extension) so that you can consume it.
+
+## Overview
+<!--+end+-->
+
+This is a few notes for using CNB image extensions.
+
+- [consume in your builder](/docs/extension-guide/consume-extension/in-builder)
+- [consume via pack build](/docs/extension-guide/consume-extension/from-cli)
+
+<!--+if false+-->
+---
+
+<a href="/docs/extension-guide/consume-extension/in-builder" class="button bg-pink">Start Tutorial</a>
+<!--+end+-->

content/docs/extension-guide/consume-extension/from-cli.md

@@ -0,0 +1,14 @@
++++
+title="Specifying an Image Extension at Build Time"
+weight=405
++++
+
+<!-- test:suite=dockerfiles;weight=5 -->
+
+### Specifying an Image Extension at Build Time
+
+No builder can be truly omniscient, and whoever did yours surely was no exception! You need to add a little extra spice to the mix with this late-breaking extension, by doing something like:
+
+`pack build [...] --extension=foo [...]`
+
+

content/docs/extension-guide/consume-extension/in-builder.md

@@ -0,0 +1,25 @@
++++
+title="Specifying an Image Extension in the Builder"
+weight=405
++++
+
+<!-- test:suite=dockerfiles;weight=5 -->
+
+### Specifying an Image Extension in the Builder
+
+You're pretty sharp, and you know what your buildpack users will need.
+That's why you're going to add something similar to the following lines directly to `builder.toml`:
+
+```
+[[order-extensions]]
+[[order-extensions.group]]
+id = "foo"
+version = "0.0.1"
+
+[[extensions]]
+id = "foo"
+version = "0.0.1"
+uri = "/local/path/to/extension/foo" # can be relative or absolute
+```
+
+