Move verify_share to return batch-verifiable statements

While the previous construction achieved n/2 average detection,
this will run in log2(n). Unfortunately, the need to keep entropy
around (or take in an RNG here) remains.

crypto/frost/src/tests/curve.rs

@@ -1,4 +1,4 @@
-use rand::{RngCore, CryptoRng};
+use rand_core::{RngCore, CryptoRng};
 
 use group::Group;
 

crypto/frost/src/tests/literal/dalek.rs

@@ -1,4 +1,4 @@
-use rand::rngs::OsRng;
+use rand_core::OsRng;
 
 use crate::{
   curve,

crypto/frost/src/tests/literal/ed448.rs

@@ -1,4 +1,4 @@
-use rand::rngs::OsRng;
+use rand_core::OsRng;
 
 use ciphersuite::Ciphersuite;
 

crypto/frost/src/tests/literal/kp256.rs

@@ -1,4 +1,4 @@
-use rand::rngs::OsRng;
+use rand_core::OsRng;
 
 use crate::tests::vectors::{Vectors, test_with_vectors};
 

crypto/frost/src/tests/mod.rs

@@ -1,6 +1,6 @@
 use std::collections::HashMap;
 
-use rand::{RngCore, CryptoRng};
+use rand_core::{RngCore, CryptoRng};
 
 pub use dkg::tests::{key_gen, recover_key};
 

crypto/frost/src/tests/vectors.rs

@@ -5,7 +5,7 @@ use std::collections::HashMap;
 use std::str::FromStr;
 
 use zeroize::Zeroizing;
-use rand::{RngCore, CryptoRng};
+use rand_core::{RngCore, CryptoRng};
 
 use group::{ff::PrimeField, GroupEncoding};