Tag along on MobArena's /ma reload command.

This commit adds to the main plugin class a tiny event listener that
listens for MobArena's post-reload event and responds by calling the
internal reload method. This gives us a super cheap way to support
reloads while giving server owners one fewer commands to worry about.

Closes #11

src/main/java/org/mobarena/stats/MobArenaStatsPlugin.java

@@ -2,10 +2,13 @@ package org.mobarena.stats;
 
 import com.garbagemule.MobArena.MobArena;
 import com.garbagemule.MobArena.commands.CommandHandler;
+import com.garbagemule.MobArena.events.MobArenaReloadEvent;
 import org.bstats.bukkit.Metrics;
 import org.bukkit.command.PluginCommand;
 import org.bukkit.configuration.ConfigurationSection;
+import org.bukkit.event.EventHandler;
 import org.bukkit.event.HandlerList;
+import org.bukkit.event.Listener;
 import org.bukkit.plugin.PluginManager;
 import org.mobarena.stats.command.ArenaStatsCommand;
 import org.mobarena.stats.command.DeleteSessionStatsCommand;
@@ -82,6 +85,7 @@ public class MobArenaStatsPlugin extends JavaPlugin implements MobArenaStats {
             setupExecutors();
             setupCommands();
             setupMetrics();
+            registerReloadListener();
         } catch (Exception up) {
             // If setup fails, we can't recover, so throw up
             throw new RuntimeException(up);
@@ -139,6 +143,15 @@ public class MobArenaStatsPlugin extends JavaPlugin implements MobArenaStats {
         metrics.addCustomChart(new StoreTypeChart(this));
     }
 
+    private void registerReloadListener() {
+        getServer().getPluginManager().registerEvents(new Listener() {
+            @EventHandler
+            public void on(MobArenaReloadEvent event) {
+                reload();
+            }
+        }, this);
+    }
+
     private void reload() {
         try {
             createSessionStore();