fix(examples): AtomicUint is deprecated in favor of AtomicUsize

Signed-off-by: Raul Gutierrez S <rgs@itevenworks.net>

examples/example_route_data.rs

@@ -1,4 +1,4 @@
-#![feature(core, io)]
+#![feature(io)]
 
 extern crate nickel;
 extern crate http;
@@ -7,11 +7,11 @@ use nickel::{
     Nickel, Request, Response, HttpRouter
 };
 use std::old_io::net::ip::Ipv4Addr;
-use std::sync::atomic::AtomicUint;
+use std::sync::atomic::AtomicUsize;
 use std::sync::atomic::Ordering::Relaxed;
 
 struct Logger {
-    visits: AtomicUint
+    visits: AtomicUsize
 }
 
 fn main() {
@@ -24,6 +24,6 @@ fn main() {
     // issue #20178
     let rhandler: fn(&Request, &mut Response, &Logger) = root_handler;
 
-    server.get("/", (rhandler, Logger{visits: AtomicUint::new(0)}));
+    server.get("/", (rhandler, Logger{visits: AtomicUsize::new(0)}));
     server.listen(Ipv4Addr(127, 0, 0, 1), 6767);
 }