Update nitrokey crate to 0.2.3

This change updates the nitrokey crate to version 0.2.3. This version
bumps the rand crate used to 0.6.1, which in turn requires an additional
set of dependencies.

Import subrepo nitrokey/:nitrokey at b3e2adc5bb1300441ca74cc7672617c042f3ea31
Import subrepo rand/:rand at 73613ff903512e9503e41cc8ba9eae76269dc598
Import subrepo rustc_version/:rustc_version at 0294f2ba2018bf7be672abd53db351ce5055fa02
Import subrepo semver-parser/:semver-parser at 750da9b11a04125231b1fb293866ca036845acee
Import subrepo semver/:semver at 5eb6db94fa03f4d5c64a625a56188f496be47598

1 files changed, 45 insertions, 0 deletions

diff --git a/rand/rand_xorshift/README.md b/rand/rand_xorshift/README.md
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+# rand_xorshift
+
+[![Build Status](https://travis-ci.org/rust-random/rand.svg)](https://travis-ci.org/rust-random/rand)
+[![Build Status](https://ci.appveyor.com/api/projects/status/github/rust-random/rand?svg=true)](https://ci.appveyor.com/project/rust-random/rand)
+[![Latest version](https://img.shields.io/crates/v/rand_xorshift.svg)](https://crates.io/crates/rand_xorshift)
+[![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)
+
+Implements the Xorshift random number generator.
+
+The Xorshift[^1] algorithm is not suitable for cryptographic purposes
+but is very fast. If you do not know for sure that it fits your
+requirements, use a more secure one such as `StdRng` or `OsRng`.
+
+[^1]: Marsaglia, George (July 2003).
+      ["Xorshift RNGs"](https://www.jstatsoft.org/v08/i14/paper).
+      *Journal of Statistical Software*. Vol. 8 (Issue 14).
+
+Links:
+
+-   [API documentation (master)](https://rust-random.github.io/rand/rand_xorshift)
+-   [API documentation (docs.rs)](https://docs.rs/rand_xorshift)
+-   [Changelog](CHANGELOG.md)
+
+[rand]: https://crates.io/crates/rand
+
+
+## Crate Features
+
+`rand_xorshift` is `no_std` compatible. It does not require any functionality
+outside of the `core` lib, thus there are no features to configure.
+
+The `serde1` feature includes implementations of `Serialize` and `Deserialize`
+for the included RNGs.
+
+
+## License
+
+`rand_xorshift` is distributed under the terms of both the MIT license and the
+Apache License (Version 2.0).
+
+See [LICENSE-APACHE](LICENSE-APACHE) and [LICENSE-MIT](LICENSE-MIT), and
+[COPYRIGHT](COPYRIGHT) for details.