Deal with the ConcurrentModification issue. Fixes #873

src/main/java/com/gmail/nossr50/runnables/party/PartyAutoKickTask.java

@@ -1,5 +1,6 @@
 package com.gmail.nossr50.runnables.party;
 
+import java.util.ArrayList;
 import java.util.Iterator;
 
 import org.bukkit.OfflinePlayer;
@@ -22,8 +23,7 @@ public class PartyAutoKickTask extends BukkitRunnable {
         for (Iterator<Party> partyIterator = PartyManager.getParties().iterator(); partyIterator.hasNext();) {
             Party party = partyIterator.next();
 
-            for (Iterator<OfflinePlayer> memberIterator = party.getMembers().iterator(); memberIterator.hasNext();) {
-                OfflinePlayer member = memberIterator.next();
+            for (OfflinePlayer member : new ArrayList<OfflinePlayer>(party.getMembers())) {
 
                 if (currentTime - member.getLastPlayed() > kickTime) {
                     PartyManager.removeFromParty(member, party);