Update Substrate (#661)

* Make compat with exit-future updates

* Update exit-future entirely

* Tidy

* Bump Substrate

polkadot/test-parachains/adder/collator/src/main.rs

@@ -145,7 +145,7 @@ fn main() {
 	let exit_send_cell = RefCell::new(Some(exit_send));
 	ctrlc::set_handler(move || {
 		if let Some(exit_send) = exit_send_cell.try_borrow_mut().expect("signal handler not reentrant; qed").take() {
-			exit_send.fire();
+			let _ = exit_send.fire();
 		}
 	}).expect("Error setting up ctrl-c handler");