[Add] AutoCleanTimer, Cleanable 增加缓存库自动清理;

[Update] HotDataCacheStore 增加对自动清理的支持;
[Change] RedisPoolCacheStore 将Redis缓存库抽象类设为default(原public);
[Change] MiraiMessageSender, BotCommandProcess 适配HotDataCacheStore的修改;
[Change] BotCommandProcess 调整ranking命令的输出格式;

src/main/java/net/lamgc/cgj/bot/cache/Cleanable.java

@@ -0,0 +1,10 @@
+package net.lamgc.cgj.bot.cache;
+
+/**
+ * 可清理接口, 实现该接口代表该类拥有清理动作.
+ */
+public interface Cleanable {
+
+    void clean() throws Exception;
+
+}