Add constraints for relevant curves (#3)

ed_on_mnt4_753/src/constraints/curves.rs

@@ -0,0 +1,12 @@
+use ark_r1cs_std::groups::curves::twisted_edwards::AffineVar;
+use crate::*;
+
+use crate::constraints::fields::FqVar;
+
+/// A variable that is the R1CS equivalent of `crate::EdwardsAffine`.
+pub type EdwardsVar = AffineVar<EdwardsParameters, FqVar>;
+
+#[test]
+fn test() {
+    ark_curve_constraint_tests::curves::te_test::<EdwardsParameters, EdwardsVar>().unwrap();
+}