xptracker: limit how often the same players are looked up

Use player rank to set how often the same player is allowed to be looked
up. Replace the ConcurrentLinkedDeque with a synchronized ArrayDeque
which has a constant time size().

http-service/src/main/resources/net/runelite/http/service/xp/schema.sql

@@ -1,8 +1,8 @@
--- MySQL dump 10.16  Distrib 10.2.9-MariaDB, for Linux (x86_64)
+-- MySQL dump 10.16  Distrib 10.2.18-MariaDB, for Linux (x86_64)
 --
 -- Host: localhost    Database: xptracker
 -- ------------------------------------------------------
--- Server version	10.2.9-MariaDB
+-- Server version       10.2.18-MariaDB
 
 /*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
 /*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
@@ -26,6 +26,8 @@ CREATE TABLE `player` (
   `id` int(11) NOT NULL AUTO_INCREMENT,
   `name` varchar(32) NOT NULL,
   `tracked_since` timestamp NOT NULL DEFAULT current_timestamp(),
+  `last_updated` timestamp NOT NULL DEFAULT current_timestamp(),
+  `rank` int(11) DEFAULT NULL,
   PRIMARY KEY (`id`),
   UNIQUE KEY `name` (`name`)
 ) ENGINE=InnoDB DEFAULT CHARSET=latin1;
@@ -116,7 +118,7 @@ CREATE TABLE `xp` (
   `overall_rank` int(11) NOT NULL,
   PRIMARY KEY (`id`),
   UNIQUE KEY `player_time` (`player`,`time`),
-  INDEX `idx_time` (`time`),
+  KEY `idx_time` (`time`),
   CONSTRAINT `fk_player` FOREIGN KEY (`player`) REFERENCES `player` (`id`)
 ) ENGINE=InnoDB DEFAULT CHARSET=latin1;
 /*!40101 SET character_set_client = @saved_cs_client */;
@@ -130,4 +132,4 @@ CREATE TABLE `xp` (
 /*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;
 /*!40111 SET SQL_NOTES=@OLD_SQL_NOTES */;
 
--- Dump completed on 2018-01-20 18:37:09
+-- Dump completed on 2019-02-15 21:01:17