Update the readme

sdk/containerregistry/azure-containers-containerregistry/README.md

@@ -1,20 +1,29 @@
 # Azure Container Registry client library for Java
-Azure Container Registry is a cloud service that lets you manage your container images and manifests.
+
+Azure Container Registry allows you to build, store, and manage container images and artifacts in a private registry for all types of container deployments.
+
+Use the client library for Azure Container Registry to:
+
+- List the repositories in a registry
+- List the images or artifacts in a repository
+
+  [Source code](https://github.com/Azure/azure-sdk-for-java/tree/master/sdk/containerregistry/azure-containers-containerregistry)
 
 ## Getting started
-<Add getting started steps..>
+
+### Install the package
+
+### Prerequisites
+
+### Authenticate the client
 
 ## Key concepts
-<Add the key concepts here.>
 
 ## Examples
-<Add examples kere>
 
 ## Troubleshooting
-<Add troubleshooting guide>
 
 ## Next steps
-<Add next steps here.>
 
 ## Contributing
-<Add contributing steps>
+<Instructions on how to contribute>.