Externalized all peers selection and handling (#468)

Moved handling to the peer map out of the p2p server and into
its own struct. Allowed factoring code from the net adapter and
simplification of some interactions. Also removes the need for
the adapter to reference the p2p server or peers.

Fixes #430, #453 and #456

api/src/handlers.rs

@@ -486,13 +486,13 @@ let _ = thread::Builder::new()
 				tx_pool: tx_pool.clone(),
 			};
 			let peers_all_handler = PeersAllHandler {
-				p2p_server: p2p_server.clone(),
+				peers: peers.clone(),
 			};
 			let peers_connected_handler = PeersConnectedHandler {
-				p2p_server: p2p_server.clone(),
+				peers: peers.clone(),
 			};
 			let peer_handler = PeerHandler {
-				p2p_server: p2p_server.clone(),
+				peers: peers.clone(),
 			};
 
 			let route_list = vec!(