Use Matcher.quoteReplacement here!

Fixes #1676 - for real this time

src/main/java/com/gmail/nossr50/chat/PartyChatManager.java

@@ -1,5 +1,6 @@
 package com.gmail.nossr50.chat;
 
+import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 import org.bukkit.ChatColor;
@@ -29,7 +30,7 @@ public class PartyChatManager extends ChatManager {
     @Override
     protected void sendMessage() {
         if (Config.getInstance().getPartyChatColorLeaderName() && senderName.equalsIgnoreCase(party.getLeader())) {
-            message = message.replaceFirst(Pattern.quote(displayName), ChatColor.GOLD + Pattern.quote(displayName) + ChatColor.RESET);
+            message = message.replaceFirst(Pattern.quote(displayName), ChatColor.GOLD + Matcher.quoteReplacement(displayName) + ChatColor.RESET);
         }
 
         for (Player member : party.getOnlineMembers()) {