Merge rust-bitcoin/rust-bitcoin#916: Adds derives to TweakedKeyPair

174a99c Implement serde for TweakedKeyPair (Dr Maxim Orlovsky)
df3297c Implement derives for TweakedKeyPair (Dr Maxim Orlovsky)

Pull request description:

  We forgot about them and marked as TODO. This is clearly an RC fix

ACKs for top commit:
  apoelstra:
    ACK 174a99c
  sanket1729:
    ACK 174a99c

Tree-SHA512: 6cd446f1b73a9f381db976dcf77d75a108e60f5a521a0d387052779be5ac98ba6b82fb3a39dc58e5529ffcc4fb2fef2a037443dc1afde8309716096f97408a78

Author: dr-orlovsky

src/util/schnorr.rs

@@ -60,9 +60,9 @@ impl fmt::Display for TweakedPublicKey {
 pub type UntweakedKeyPair = ::KeyPair;
 
 /// Tweaked BIP-340 key pair
-#[derive(Clone)]
-#[cfg_attr(feature = "std", derive(Debug))]
-// TODO: Add other derives once secp256k1 v0.21.3 released
+#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg_attr(feature = "serde", serde(transparent))]
 pub struct TweakedKeyPair(::KeyPair);
 
 /// A trait for tweaking BIP340 key types (x-only public keys and key pairs).