Update to proc_macro

Author: dtolnay

README.md

@@ -62,7 +62,7 @@ serde_derive = "0.8"
 Then run:
 
 ```rust
-#![feature(rustc_macro)]
+#![feature(proc_macro)]
 
 #[macro_use]
 extern crate serde_derive;

json_tests/benches/bench.rs

@@ -1,7 +1,7 @@
 #![cfg_attr(feature = "nightly-testing", feature(plugin))]
 #![cfg_attr(feature = "nightly-testing", plugin(clippy))]
 
-#![cfg_attr(not(feature = "with-syntex"), feature(rustc_macro))]
+#![cfg_attr(not(feature = "with-syntex"), feature(proc_macro))]
 
 #![feature(test)]
 

json_tests/tests/test.rs

@@ -1,7 +1,7 @@
 #![cfg_attr(feature = "nightly-testing", feature(plugin))]
 #![cfg_attr(feature = "nightly-testing", plugin(clippy))]
 
-#![cfg_attr(not(feature = "with-syntex"), feature(rustc_macro, plugin))]
+#![cfg_attr(not(feature = "with-syntex"), feature(proc_macro, plugin))]
 #![cfg_attr(not(feature = "with-syntex"), plugin(indoc))]
 
 #[cfg(not(feature = "with-syntex"))]