Directory Restructure (#1163)

* Move tests -> testing

* Directory restructure

* Update Cargo.toml during restructure

* Update Makefile during restructure

* Fix arbitrary path

crypto/bls/src/keypair.rs

@@ -0,0 +1,42 @@
+use super::{PublicKey, SecretKey};
+use serde_derive::{Deserialize, Serialize};
+use std::fmt;
+use std::hash::{Hash, Hasher};
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct Keypair {
+    pub sk: SecretKey,
+    pub pk: PublicKey,
+}
+
+impl Keypair {
+    /// Instantiate a Keypair using SecretKey::random().
+    pub fn random() -> Self {
+        let sk = SecretKey::random();
+        let pk = PublicKey::from_secret_key(&sk);
+        Keypair { sk, pk }
+    }
+
+    pub fn identifier(&self) -> String {
+        self.pk.concatenated_hex_id()
+    }
+}
+
+#[allow(clippy::derive_hash_xor_eq)]
+impl Hash for Keypair {
+    /// Note: this is distinct from consensus serialization, it will produce a different hash.
+    ///
+    /// This method uses the uncompressed bytes, which are much faster to obtain than the
+    /// compressed bytes required for consensus serialization.
+    ///
+    /// Use `ssz::Encode` to obtain the bytes required for consensus hashing.
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.pk.as_uncompressed_bytes().hash(state)
+    }
+}
+
+impl fmt::Display for Keypair {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.pk)
+    }
+}