Add v1 deprecation notes to README (#28)

* Add v1 deprecation notes to README

* Add blurb about how to migrate from v1 to v2

* Add date for v1 route deprecation

README.md

@@ -29,6 +29,16 @@ LISA was inspired by another AWS open source project [aws-genai-llm-chatbot](htt
 2.  LISA is designed to be composable so we've separated the the underlying LLM serving capability, this repository contains, LISA-Serve and the chat frontend, LISA-Chat, which are deployable as separate stacks.
 3.  LISA is designed to support the OpenAI specification, so anywhere you can use the OpenAI API in your applications, you can insert LISA in its place.
 
+## Deprecation Notes
+
+With the release of the LISA v2.0.0 we have deprecated the v1 endpoint routes in LISA Serve. These routes, such as the `/v1/openai` route, will still work in the current v2 release, but we actively encourage users to migrate to the v2 endpoints
+as they will have greater support for listing and using models, along with greater support for the OpenAI API specification.
+
+We intend to fully remove the v1 routes in the next release of LISA, anticipating July 2024.
+
+For users dependent on the v1 OpenAI endpoint, all you have to do to migrate is change your base URL route from `/v1/openai` to `/v2/serve`. Please note that model names may change once you list models again, but this comes with the benefit of being
+able to list both models hosted by LISA and models that are configured with the new LiteLLM configuration options.
+
 ## Getting Started
 
 LISA leverages AWS's cloud development toolkit (cdk). Users of LISA should be familiar with CDK and infrastructure-as-code principles. If CDK is new to you please see the [documentation on CDK](https://docs.aws.amazon.com/cdk/v2/guide/getting_started.html) and talk to your AWS support team to help get you started.
@@ -368,7 +378,7 @@ in the following snippet.
 ```bash
 lisa_serve_rest_url="https://<rest-url-from-cdk-output>"
 token_string="YOUR_STRING_HERE"
-curl ${lisa_serve_rest_url}/v1/openai/models \
+curl ${lisa_serve_rest_url}/v2/serve/models \
     -H 'accept: application/json' \
     -H 'Content-Type: application/json' \
     -H 'Api-Key: '${token_string}