Remove qeustion marks

src/bin/getty.rs

@@ -1,5 +1,3 @@
-#![feature(question_mark)]
-
 extern crate syscall;
 
 use std::io::Write;

src/bin/login.rs

@@ -1,5 +1,3 @@
-#![feature(question_mark)]
-
 extern crate termion;
 extern crate userutils;
 

src/bin/su.rs

@@ -1,5 +1,3 @@
-#![feature(question_mark)]
-
 extern crate syscall;
 extern crate termion;
 extern crate userutils;

src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(question_mark)]
-
 extern crate octavo;
 
 use octavo::octavo_digest::Digest;