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

5 files changed, 33 insertions, 34 deletions

diff --git a/rand/rand_xorshift/CHANGELOG.md b/rand/rand_xorshift/CHANGELOG.md
index 539af41..ce3098a 100644
--- a/rand/rand_xorshift/CHANGELOG.md
+++ b/rand/rand_xorshift/CHANGELOG.md
@@ -4,6 +4,14 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.2.0] - 2019-06-12
+- Bump minor crate version since rand_core bump is a breaking change
+- Switch to Edition 2018
+
+## [0.1.2] - 2019-06-06 - yanked
+- Bump `rand_core` version
+- Make XorShiftRng::from_rng portable by enforcing Endianness (#815)
+
 ## [0.1.1] - 2019-01-04
 - Reorganise code and tests; tweak doc
 
diff --git a/rand/rand_xorshift/Cargo.toml b/rand/rand_xorshift/Cargo.toml
index 114fee9..9cb257b 100644
--- a/rand/rand_xorshift/Cargo.toml
+++ b/rand/rand_xorshift/Cargo.toml
@@ -1,29 +1,29 @@
 [package]
 name = "rand_xorshift"
-version = "0.1.1"
+version = "0.2.0"
 authors = ["The Rand Project Developers", "The Rust Project Developers"]
-license = "MIT/Apache-2.0"
+license = "MIT OR Apache-2.0"
 readme = "README.md"
 repository = "https://github.com/rust-random/rand"
-documentation = "https://rust-random.github.io/rand/rand_xorshift"
+documentation = "https://rust-random.github.io/rand/rand_xorshift/"
 homepage = "https://crates.io/crates/rand_xorshift"
 description = """
 Xorshift random number generator
 """
 keywords = ["random", "rng", "xorshift"]
 categories = ["algorithms", "no-std"]
+edition = "2018"
 
 [badges]
 travis-ci = { repository = "rust-random/rand" }
 appveyor = { repository = "rust-random/rand" }
 
 [features]
-serde1 = ["serde", "serde_derive"]
+serde1 = ["serde"]
 
 [dependencies]
-rand_core = { path = "../rand_core", version = ">=0.2, <0.4", default-features=false }
-serde = { version = "1", optional = true }
-serde_derive = { version = "^1.0.38", optional = true }
+rand_core = { path = "../rand_core", version = "0.5" }
+serde = { version = "1", features = ["derive"], optional = true }
 
 [dev-dependencies]
 # This is for testing serde, unfortunately we can't specify feature-gated dev
diff --git a/rand/rand_xorshift/README.md b/rand/rand_xorshift/README.md
index 573ee12..57de284 100644
--- a/rand/rand_xorshift/README.md
+++ b/rand/rand_xorshift/README.md
@@ -6,7 +6,7 @@
 [![Book](https://img.shields.io/badge/book-master-yellow.svg)](https://rust-random.github.io/book/)
 [![API](https://img.shields.io/badge/api-master-yellow.svg)](https://rust-random.github.io/rand/rand_xorshift)
 [![API](https://docs.rs/rand_xorshift/badge.svg)](https://docs.rs/rand_xorshift)
-[![Minimum rustc version](https://img.shields.io/badge/rustc-1.22+-lightgray.svg)](https://github.com/rust-random/rand#rust-version-requirements)
+[![Minimum rustc version](https://img.shields.io/badge/rustc-1.32+-lightgray.svg)](https://github.com/rust-random/rand#rust-version-requirements)
 
 Implements the Xorshift random number generator.
 
@@ -22,7 +22,7 @@ Links:
 
 -   [API documentation (master)](https://rust-random.github.io/rand/rand_xorshift)
 -   [API documentation (docs.rs)](https://docs.rs/rand_xorshift)
--   [Changelog](CHANGELOG.md)
+-   [Changelog](https://github.com/rust-random/rand/blob/master/rand_xorshift/CHANGELOG.md)
 
 [rand]: https://crates.io/crates/rand
 
diff --git a/rand/rand_xorshift/src/lib.rs b/rand/rand_xorshift/src/lib.rs
index db42ba2..b9fef23 100644
--- a/rand/rand_xorshift/src/lib.rs
+++ b/rand/rand_xorshift/src/lib.rs
@@ -17,14 +17,10 @@
 
 #![no_std]
 
-pub extern crate rand_core;
-
-#[cfg(feature="serde1")] extern crate serde;
-#[cfg(feature="serde1")] #[macro_use] extern crate serde_derive;
-
 use core::num::Wrapping as w;
-use core::{fmt, slice};
+use core::fmt;
 use rand_core::{RngCore, SeedableRng, Error, impls, le};
+#[cfg(feature="serde1")] use serde::{Serialize, Deserialize};
 
 /// An Xorshift random number generator.
 ///
@@ -75,7 +71,8 @@ impl RngCore for XorShiftRng {
     }
 
     fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
-        Ok(self.fill_bytes(dest))
+        self.fill_bytes(dest);
+        Ok(())
     }
 }
 
@@ -102,22 +99,19 @@ impl SeedableRng for XorShiftRng {
     }
 
     fn from_rng<R: RngCore>(mut rng: R) -> Result<Self, Error> {
-        let mut seed_u32 = [0u32; 4];
+        let mut b = [0u8; 16];
         loop {
-            unsafe {
-                let ptr = seed_u32.as_mut_ptr() as *mut u8;
-
-                let slice = slice::from_raw_parts_mut(ptr, 4 * 4);
-                rng.try_fill_bytes(slice)?;
+            rng.try_fill_bytes(&mut b[..])?;
+            if !b.iter().all(|&x| x == 0) {
+                break;
             }
-            if !seed_u32.iter().all(|&x| x == 0) { break; }
         }
 
         Ok(XorShiftRng {
-            x: w(seed_u32[0]),
-            y: w(seed_u32[1]),
-            z: w(seed_u32[2]),
-            w: w(seed_u32[3]),
+            x: w(u32::from_le_bytes([b[0], b[1], b[2], b[3]])),
+            y: w(u32::from_le_bytes([b[4], b[5], b[6], b[7]])),
+            z: w(u32::from_le_bytes([b[8], b[9], b[10], b[11]])),
+            w: w(u32::from_le_bytes([b[12], b[13], b[14], b[15]])),
         })
     }
 }
diff --git a/rand/rand_xorshift/tests/mod.rs b/rand/rand_xorshift/tests/mod.rs
index 8374b64..7ecdeae 100644
--- a/rand/rand_xorshift/tests/mod.rs
+++ b/rand/rand_xorshift/tests/mod.rs
@@ -1,7 +1,3 @@
-extern crate rand_core;
-extern crate rand_xorshift;
-#[cfg(all(feature="serde1", test))] extern crate bincode;
-
 use rand_core::{RngCore, SeedableRng};
 use rand_xorshift::XorShiftRng;
 
@@ -12,9 +8,10 @@ fn test_xorshift_construction() {
     let mut rng1 = XorShiftRng::from_seed(seed);
     assert_eq!(rng1.next_u64(), 4325440999699518727);
 
-    let _rng2 = XorShiftRng::from_rng(rng1).unwrap();
-    // Note: we cannot test the state of _rng2 because from_rng does not
-    // fix Endianness. This is allowed in the trait specification.
+    let mut rng2 = XorShiftRng::from_rng(&mut rng1).unwrap();
+    // Yes, this makes rng2 a clone of rng1!
+    assert_eq!(rng1.next_u64(), 15614385950550801700);
+    assert_eq!(rng2.next_u64(), 15614385950550801700);
 }
 
 #[test]