Add Pallas and Vesta curves (#21)

Co-authored-by: Ying Tong Lai <yingtong@electriccoin.co>
Co-authored-by: Daira Hopwood <daira@jacaranda.org>
Co-authored-by: Pratyush Mishra <pratyushmishra@berkeley.edu>
Co-authored-by: therealyingtong <yingtong@z.cash>

vesta/src/fields/fq.rs

@@ -0,0 +1 @@
+pub use ark_pallas::{Fr as Fq, FrParameters as FqParameters};

vesta/src/fields/fr.rs

@@ -0,0 +1 @@
+pub use ark_pallas::{Fq as Fr, FqParameters as FrParameters};

vesta/src/fields/mod.rs

@@ -0,0 +1,8 @@
+pub mod fq;
+pub use self::fq::*;
+
+pub mod fr;
+pub use self::fr::*;
+
+#[cfg(test)]
+mod tests;

vesta/src/fields/tests.rs

@@ -0,0 +1,26 @@
+use ark_std::test_rng;
+use rand::Rng;
+
+use crate::*;
+
+use ark_curve_tests::fields::*;
+
+#[test]
+fn test_fr() {
+    let mut rng = test_rng();
+    let a: Fr = rng.gen();
+    let b: Fr = rng.gen();
+    field_test(a, b);
+    sqrt_field_test(a);
+    primefield_test::<Fr>();
+}
+
+#[test]
+fn test_fq() {
+    let mut rng = test_rng();
+    let a: Fq = rng.gen();
+    let b: Fq = rng.gen();
+    field_test(a, b);
+    sqrt_field_test(a);
+    primefield_test::<Fq>();
+}