message: Add trust-dns feature in README
diff: @@ -32,7 +32,9 @@ shadowsocks is a fast tunnel proxy that helps you bypass firewalls.
  * `single-threaded` - Let `sslocal` and `ssserver` run in single threaded mode (by using Tokio's `basic_scheduler`).
  -Default features: `["sodium", "rc4", "aes-cfb", "aes-ctr"]`.
  +* `trust-dns` - Uses [`trust-dns-resolver`](https://crates.io/crates/trust-dns-resolver) as DNS resolver instead of `tokio`'s builtin.
  +
  +Default features: `["sodium", "rc4", "aes-cfb", "aes-ctr", "trust-dns"]`.
  NOTE: To disable dependency of OpenSSL, just disable feature `rc4`, `aes-cfb`, `aes-ctr`, `camellia-cfb`.
  