update from rand_os to fix warnings

librustzcash/Cargo.toml

@@ -24,6 +24,5 @@ pairing = { path = "../pairing" }
 lazy_static = "1"
 byteorder = "1"
 rand_core = "0.5"
-rand_os = "0.2"
 zcash_primitives = { path = "../zcash_primitives" }
 zcash_proofs = { path = "../zcash_proofs" }

librustzcash/src/rustzcash.rs

@@ -24,8 +24,7 @@ use blake2s_simd::Params as Blake2sParams;
 
 use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
 
-use rand_core::RngCore;
-use rand_os::OsRng;
+use rand_core::{OsRng, RngCore};
 use std::io::BufReader;
 
 use libc::{c_char, c_uchar, size_t};

librustzcash/src/tests/key_agreement.rs

@@ -1,7 +1,6 @@
 use ff::{PrimeField, PrimeFieldRepr};
 use pairing::bls12_381::Bls12;
-use rand_core::RngCore;
-use rand_os::OsRng;
+use rand_core::{OsRng, RngCore};
 use zcash_primitives::jubjub::{edwards, JubjubBls12};
 use zcash_primitives::primitives::{Diversifier, ViewingKey};