fixed typos

performance/src/application.rs

@@ -220,7 +220,7 @@ pub trait ApplicationLayer: Sized {
     /// the update could not be made.
     /// The implementor is free to choose how to apply these updates to storage.
     ///
-    /// If this returns `Err(IoError)`, the packet which triggered this function to be called will be
+    /// If this returns `Err(())`, the packet which triggered this function to be called will be
     /// dropped, and no session state will be mutated, preserving synchronization. The remote peer
     /// will eventually resend that packet and so this function will be called again.
     ///

performance/src/zeta.rs

@@ -651,7 +651,7 @@ pub(crate) fn received_x2_trans<Crypto: CryptoLayer, App: ApplicationLayer<Crypt
         drop(ekem1_secret);
         i = k;
         // We attempt to decrypt the payload at most three times. First two times with
-        // the ratchet key Alice remembers, and final time with a ratchet
+        // the ratchet keys Alice remembers, and final time with a ratchet
         // key of zero if Alice allows ratchet downgrades.
         // The following code is not constant time, meaning we leak to an
         // attacker whether or not we downgraded.