Merge 'use's in 'hello_2018' example.

examples/hello_2018/src/main.rs

@@ -1,8 +1,7 @@
 #![feature(plugin, decl_macro, proc_macro_non_items)]
 #![plugin(rocket_codegen)]
 
-use rocket;
-use rocket::routes;
+use rocket::{self, routes};
 
 #[cfg(test)] mod tests;
 

examples/hello_2018/src/tests.rs

@@ -1,6 +1,4 @@
-use rocket;
-use rocket::routes;
-use rocket::local::Client;
+use rocket::{self, routes, local::Client};
 
 #[test]
 fn hello_world() {