Print out shard ID assignment result upon startup

This makes it easier to support node operators.

cmd/harmony/main.go

@@ -466,6 +466,10 @@ func main() {
 			initialAccount.ShardID = uint32(shardIDBig.Uint64())
 		}
 	}
+	fmt.Printf("%s mode; node key %s -> shard %d\n",
+		map[bool]string{false: "Legacy", true: "Staking"}[*stakingFlag],
+		nodeconfig.GetDefaultConfig().ConsensusPubKey.SerializeToHexStr(),
+		initialAccount.ShardID)
 
 	if *nodeType != "validator" && *shardID >= 0 {
 		utils.Logger().Info().