Migrate node (cli, executor, primitives and runtime) to the 2018 edition (#1589)

substrate/node/runtime/wasm/Cargo.toml

@@ -2,6 +2,7 @@
 name = "node-runtime-wasm"
 version = "0.1.0"
 authors = ["Parity Technologies <admin@parity.io>"]
+edition = "2018"
 
 [lib]
 name = "node_runtime"

substrate/node/runtime/wasm/src/lib.rs

@@ -18,5 +18,4 @@
 
 #![cfg_attr(not(feature = "std"), no_std)]
 
-extern crate node_runtime;
 pub use node_runtime::*;