tty: add keypress event for backwards-compat

lib/tty.js

@@ -48,6 +48,8 @@ function ReadStream(fd) {
   this.readable = true;
   this.writable = false;
   this.isRaw = false;
+  // backwards-compat
+  require('readline').emitKeypressEvents(this);
 }
 inherits(ReadStream, net.Socket);