update deployment

README.md

@@ -36,7 +36,8 @@ Each line points at the package that implements it.
 
 Requirements: Go 1.27 (the `go` directive in `go.mod`), Node 22 for the console
 build, and a privileged port (53/443/853) or `CAP_NET_BIND_SERVICE` for the
-default listener set.
+default listener set. Listener addresses are configurable; high ports can be
+used when the process should not need that capability.
 
 ```sh
 git clone <this repository> fancy-dns && cd fancy-dns