• Add Request::try_clone() method.
• Add HTTP2 window size configuration to ClientBuilder.
• Add Body::as_bytes() method.
• Add Response::bytes() method for WASM target.
• Add RequestBuilder::body() method for WASM target.
• Change to enable system/environment proxy detection by default.
• Fix checking HTTP_PROXY environment variable if it the environment is from a CGI script.
• Fix removal of username/password of parsed proxy URL.
• Fix pinning async-compression dependency to last alpha.