Added McMMOPartyChangeEvent for API usage - fires whenever a player

joins or leaves a party

src/main/java/com/gmail/nossr50/events/party/McMMOPartyChangeEvent.java

@@ -0,0 +1,65 @@
+package com.gmail.nossr50.events.party;
+
+import org.bukkit.entity.Player;
+import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
+import org.bukkit.event.player.PlayerEvent;
+
+public class McMMOPartyChangeEvent extends PlayerEvent implements Cancellable{
+
+    protected String oldParty;
+    protected String newParty;
+    protected EventReason reason;
+    protected boolean cancelled;
+
+    public McMMOPartyChangeEvent(Player player, String oldParty, String newParty, EventReason reason) {
+        super(player);
+        newParty = newParty.replace(":", ".");
+        this.oldParty = oldParty;
+        this.newParty = newParty;
+        this.reason = reason;
+        this.cancelled = false;
+    }
+
+    public String getOldParty() {
+        return oldParty;
+    }
+
+    public String getNewParty() {
+        return newParty;
+    }
+
+    public EventReason getReason() {
+        return reason;
+    }
+
+    /** Rest of file is required boilerplate for custom events **/
+    private static final HandlerList handlers = new HandlerList();
+
+    @Override
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+
+    /** Following are required for Cancellable **/
+    @Override
+    public boolean isCancelled() {
+        return cancelled;
+    }
+
+    @Override
+    public void setCancelled(boolean cancelled) {
+        this.cancelled = cancelled;
+    }
+
+    public enum EventReason{
+        JOINED_PARTY,
+        LEFT_PARTY,
+        KICKED_FROM_PARTY,
+        CHANGED_PARTIES;
+    }
+}