Fixes to support Asio changes (API Change):

This adjusts Beast's interfaces and implementation to match
the changes in Boost.Asio.

example/http/client/sync/http_client_sync.cpp

@@ -53,14 +53,14 @@ int main(int argc, char** argv)
         net::io_context ioc;
 
         // These objects perform our I/O
-        tcp::resolver resolver{ioc};
-        tcp::socket socket{ioc};
+        tcp::resolver resolver(ioc);
+        beast::tcp_stream stream(ioc);
 
         // Look up the domain name
         auto const results = resolver.resolve(host, port);
 
         // Make the connection on the IP address we get from a lookup
-        net::connect(socket, results.begin(), results.end());
+        beast::connect(stream, results);
 
         // Set up an HTTP GET request message
         http::request<http::string_body> req{http::verb::get, target, version};
@@ -68,7 +68,7 @@ int main(int argc, char** argv)
         req.set(http::field::user_agent, BOOST_BEAST_VERSION_STRING);
 
         // Send the HTTP request to the remote host
-        http::write(socket, req);
+        http::write(stream, req);
 
         // This buffer is used for reading and must be persisted
         beast::flat_buffer buffer;
@@ -77,14 +77,14 @@ int main(int argc, char** argv)
         http::response<http::dynamic_body> res;
 
         // Receive the HTTP response
-        http::read(socket, buffer, res);
+        http::read(stream, buffer, res);
 
         // Write the message to standard out
         std::cout << res << std::endl;
 
         // Gracefully close the socket
         beast::error_code ec;
-        socket.shutdown(tcp::socket::shutdown_both, ec);
+        stream.socket().shutdown(tcp::socket::shutdown_both, ec);
 
         // not_connected happens sometimes
         // so don't bother reporting it.