Strategies for the send protocol

Description

This builds on top of the previous block-per-block exchange protocol by taking a list of blocks and allowing the choice of which peer to send each block to based on a strategy.

We implement two strategies on the trait, which are Random and Round-Robin.

src/dragoon_network.rs

@@ -1531,9 +1531,8 @@ where {
                     .position(|iter_peer_id| *iter_peer_id == peer_id)
                 {
                     accepted_peers.remove(index); //using swap_remove would mess up the order and doesn't ensure all peers get an equivalent number of blocks
-                    match accepted_peers_index.checked_sub(1) {
-                        Some(res) => *accepted_peers_index = res,
-                        None => {}
+                    if let Some(res) = accepted_peers_index.checked_sub(1) {
+                        *accepted_peers_index = res
                     };
                 } else {
                     debug!(