Bump codec (#786)

* Bump codec

* Fix tests

substrate/srml/executive/src/lib.rs

@@ -206,7 +206,9 @@ impl<
 		// remove temporaries.
 		let new_header = <system::Module<System>>::finalise();
 
-		// check digest
+		// check digest. uncomment next two lines to figure out next digest hash for tests.
+//		runtime_io::print(&header.digest().encode()[..]);
+//		runtime_io::print(&new_header.digest().encode()[..]);
 		assert!(header.digest() == new_header.digest());
 
 		// check storage root.