Update nitrokey crate to 0.4.0

This change finally updates the version of the nitrokey crate that we
consume to 0.4.0. Along with that we update rand_core, one of its
dependencies, to 0.5.1. Further more we add cfg-if in version 0.1.10 and
getrandom in version 0.1.13, both of which are now new (non-development)
dependencies.

Import subrepo nitrokey/:nitrokey at e81057037e9b4f370b64c0a030a725bc6bdfb870
Import subrepo cfg-if/:cfg-if at 4484a6faf816ff8058088ad857b0c6bb2f4b02b2
Import subrepo getrandom/:getrandom at d661aa7e1b8cc80b47dabe3d2135b3b47d2858af
Import subrepo rand/:rand at d877ed528248b52d947e0484364a4e1ae59ca502

1 files changed, 3 insertions, 7 deletions

diff --git a/rand/examples/monty-hall.rs b/rand/examples/monty-hall.rs
index 0932c5e..9fe5839 100644
--- a/rand/examples/monty-hall.rs
+++ b/rand/examples/monty-hall.rs
@@ -26,13 +26,10 @@
 //!
 //! [Monty Hall Problem]: https://en.wikipedia.org/wiki/Monty_Hall_problem
 
-#![cfg(feature="std")]
+#![cfg(feature = "std")]
 
-
-extern crate rand;
-
-use rand::Rng;
 use rand::distributions::{Distribution, Uniform};
+use rand::Rng;
 
 struct SimulationResult {
     win: bool,
@@ -40,8 +37,7 @@ struct SimulationResult {
 }
 
 // Run a single simulation of the Monty Hall problem.
-fn simulate<R: Rng>(random_door: &Uniform<u32>, rng: &mut R)
-                    -> SimulationResult {
+fn simulate<R: Rng>(random_door: &Uniform<u32>, rng: &mut R) -> SimulationResult {
     let car = random_door.sample(rng);
 
     // This is our initial choice