Revert-revert migrate to ed25519-dalek crate (#3877)

* Revert "Revert "Migrate from ring to ed25519-dalek, take 2 (#3844)" (#3868)"

This reverts commit 6a878602f2.

* Fix Signature::verify method

core/tests/tvu.rs

@@ -171,7 +171,7 @@ fn test_replay() {
         // receive retransmitted messages
         let timer = Duration::new(1, 0);
         while let Ok(_msg) = r_reader.recv_timeout(timer) {
-            trace!("got msg");
+            info!("got msg");
         }
 
         let working_bank = bank_forks.read().unwrap().working_bank();