Remove use_extern_macros features

This has now been stabilized!

examples/add/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/asm.js/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/canvas/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate js_sys;
 extern crate wasm_bindgen;
 extern crate web_sys;

examples/char/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/closures/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 extern crate js_sys;
 

examples/comments/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/console_log/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 extern crate web_sys;
 

examples/dom/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/guide-supported-types-examples/src/lib.rs

@@ -1,4 +1,3 @@
-#![feature(use_extern_macros)]
 #![allow(unused_variables, dead_code)]
 
 extern crate wasm_bindgen;

examples/hello_world/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/import_js/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/julia_set/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 use wasm_bindgen::prelude::*;
 

examples/math/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/no_modules/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/performance/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate humantime;
 extern crate wasm_bindgen;
 

examples/smorgasboard/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/wasm-in-wasm/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(use_extern_macros)]
-
 extern crate wasm_bindgen;
 
 use wasm_bindgen::prelude::*;

examples/webaudio/src/lib.rs

@@ -1,4 +1,4 @@
-#![feature(use_extern_macros, nll)]
+#![feature(nll)]
 
 extern crate wasm_bindgen;
 extern crate web_sys;
@@ -144,4 +144,4 @@ impl FmOsc {
     }
 
 
-}
+}