Don't use peers.iter().next() in bodysync

- We don't actually need to mutate this value at all.  We can just take the peer by index
- This also removes cycle behavior in bodysync as it pertains to peerlist polling
- Result is that we request 1 block from 1 peer, at a given time

servers/src/epic/sync/body_sync.rs

@@ -135,15 +135,17 @@ impl BodySync {
 			self.blocks_requested = 0;
 			self.receive_timeout = Utc::now() + Duration::seconds(6);
 
-			let mut peers_iter = peers.iter().cycle();
+			let mut peer_idx = 0;
 			for hash in hashes_to_get.clone() {
-				if let Some(peer) = peers_iter.next() {
-					if let Err(e) = peer.send_block_request(*hash, chain::Options::SYNC) {
-						debug!("Skipped request to {}: {:?}", peer.info.addr, e);
-						peer.stop();
-					} else {
-						self.blocks_requested += 1;
-					}
+				if let Err(e) = peers[peer_idx].send_block_request(*hash, chain::Options::SYNC) {
+					debug!("Skipped request to {}: {:?}", peers[peer_idx].info.addr, e);
+					peers[peer_idx].stop();
+				} else {
+					self.blocks_requested += 1;
+				}
+				peer_idx += 1;
+				if peer_idx == peers.len() {
+					break;
 				}
 			}
 		}