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, 0 insertions, 51 deletions

diff --git a/rand/rand-derive/README.md b/rand/rand-derive/README.md
deleted file mode 100644
index 3d1fedb..0000000
--- a/rand/rand-derive/README.md
+++ /dev/null
@@ -1,51 +0,0 @@
-
-rand_macros
-====
-
-`#[derive(Rand)]` functionality for the `rand::Rand` trait.
-
-## Usage
-Add this to your `Cargo.toml`:
-
-```toml
-[dependencies]
-rand = "0.4"
-rand_macros = "0.2"
-```
-
-and this to your crate root:
-
-```rust
-extern crate rand;
-#[macro_use]
-extern crate rand_macros;
-```
-
-## Examples
-
-`#[derive(Rand)]` can be used on any `struct` or `enum` where all fields/variants implement `rand::Rand`.
-
-```rust
-#[derive(Debug, Rand)]
-struct Foo {
-    x: u16,
-    y: Option<f64>,
-}
-
-#[derive(Debug, Rand)]
-enum Bar {
-     X{x: u8, y: isize},
-     Y([bool; 4]),
-     Z,
-}
-```
-Now you can call the `Rng::gen()` function on your custom types.
-
-```rust
-use rand::Rng;
-
-let mut rng = rand::thread_rng();
-
-println!("{:?}", rng.gen::<Foo>());
-println!("{:?}", rng.gen::<Bar>());
-```