Prepare CHANGELOG for release (#8)

CHANGELOG.md

@@ -1,11 +1,11 @@
 # Release History
 
-## 2.0.0-beta.1 (Unreleased)
+## 2.0.0-beta.1 (2024-06-06)
 
 ### Features Added
 
-### Breaking Changes
+This is the official OpenAI client library for C# / .NET. It provides convenient access to the OpenAI REST API from .NET applications and supports all the latest features. It is generated from our [OpenAPI specification](https://github.com/openai/openai-openapi) in collaboration with Microsoft.
 
-### Bugs Fixed
+### Breaking Changes
 
-### Other Changes
+If you are a user migrating from version 1.11.0 or earlier, we will soon share a migration guide to help you get started.

README.md

@@ -24,7 +24,7 @@ Note that the code examples included below were written using [.NET 8](https://d
 
 ## Using the client library
 
-The full API of this library can be found in the [api.md](https://github.com/openai/openai-dotnet/api/api.md) file, and there are many [code examples](https://github.com/openai/openai-dotnet/examples) to help. For instance, the following snippet illustrates the basic use of the chat completions API:
+The full API of this library can be found in the [api.md](https://github.com/openai/openai-dotnet/blob/main/api/api.md) file, and there are many [code examples](https://github.com/openai/openai-dotnet/tree/main/examples) to help. For instance, the following snippet illustrates the basic use of the chat completions API:
 
 ```csharp
 using OpenAI.Chat;