Update proxy-server for HB2 (#65)

* Update proxy-server for HB2

* Update README

* Remove HB prefix

* Use 2.0 beta

README.md

@@ -9,6 +9,7 @@ Examples converted to Hummingbird 2.0
 - [html-form](https://github.com/hummingbird-project/hummingbird-examples/tree/main/html-form) - Link HTML form to Hummingbird application.
 - [http2](https://github.com/hummingbird-project/hummingbird-examples/tree/main/http2) - Basic application with HTTP2 upgrade added.
 - [jobs](https://github.com/hummingbird-project/hummingbird-examples/tree/main/jobs) - Demonstrating offloading of jobs to another server.
+- [proxy-server](https://github.com/hummingbird-project/hummingbird-examples/tree/main/proxy-server) - Using AsyncHTTPClient to build a proxy server
 - [sessions](https://github.com/hummingbird-project/hummingbird-examples/tree/main/sessions) - Username/password and session authentication.
 - [todos-dynamodb](https://github.com/hummingbird-project/hummingbird-examples/tree/main/todos-dynamodb) - Todos application, based off [TodoBackend](http://todobackend.com) spec, using DynamoDB.
 - [todos-lambda](https://github.com/hummingbird-project/hummingbird-examples/tree/main/todos-lambda) - Todos application, based off [TodoBackend](http://todobackend.com) spec, using DynamoDB and running on AWS Lambda.
@@ -26,8 +27,6 @@ Examples still working with Hummingbird 1.0
 - [auth-srp](https://github.com/hummingbird-project/hummingbird-examples/tree/main/auth-srp) - Secure Remote Password authentication.
 - [ios-image-server](https://github.com/hummingbird-project/hummingbird-examples/tree/main/ios-image-server) - iOS web server that provides access to iPhone photo library.
 - [multipart-form](https://github.com/hummingbird-project/hummingbird-examples/tree/main/multipart-form) - HTML form using Multipart form data, using MultipartKit
-- [proxy-server](https://github.com/hummingbird-project/hummingbird-examples/tree/main/proxy-server) - Using AsyncHTTPClient to build a proxy server
-- [proxy-server-core](https://github.com/hummingbird-project/hummingbird-examples/tree/main/proxy-server-core) - Version of proxy server only using HummingbirdCore
 - [todos-fluent](https://github.com/hummingbird-project/hummingbird-examples/tree/main/todos-fluent) - Todos application, based off [TodoBackend](http://todobackend.com) spec, using Fluent
 - [upload-s3](https://github.com/hummingbird-project/hummingbird-examples/tree/main/upload-s3) - File uploading and downloading using AWS S3 as backing store.
 - [websocket-chat](https://github.com/hummingbird-project/hummingbird-examples/tree/main/websocket-chat) - Simple chat application using WebSockets.