fix http_connector

1. use ipv4 first when connect to http server.
2. allow redirect to url like: http://tcp://p.com:11010
3. dns should also use long timeout

easytier/src/connector/dns_connector.rs

@@ -1,14 +1,8 @@
-use std::{
-    net::SocketAddr,
-    pin::Pin,
-    sync::{Arc, RwLock},
-};
+use std::{net::SocketAddr, sync::Arc};
 
 use crate::{
     common::{error::Error, global_ctx::ArcGlobalCtx},
-    tunnel::{
-        Tunnel, TunnelConnector, TunnelError, ZCPacketSink, ZCPacketStream, PROTO_PORT_OFFSET,
-    },
+    tunnel::{Tunnel, TunnelConnector, TunnelError, PROTO_PORT_OFFSET},
 };
 use anyhow::Context;
 use dashmap::DashSet;