Add a method to get an important mode comparator.

common/src/com/dmdirc/parser/interfaces/ChannelClientInfo.java

 
 package com.dmdirc.parser.interfaces;
 
+import java.util.Comparator;
 import java.util.Map;
 
 /**
      */
     void kick(String message);
 
+    /**
+     * Gets a comparator to compare important prefix modes.
+     *
+     * @return Important mode comparator
+     */
+    Comparator<String> getImportantModeComparator();
+
 }

irc/src/com/dmdirc/parser/irc/IRCChannelClientInfo.java

 import com.dmdirc.parser.interfaces.ChannelClientInfo;
 import com.dmdirc.parser.interfaces.ChannelInfo;
 
+import java.util.Comparator;
 import java.util.HashMap;
 import java.util.Map;
 
         return modeManager.compareImportantModes(getAllModes(), arg0.getAllModes());
     }
 
+    @Override
+    public Comparator<String> getImportantModeComparator() {
+        return modeManager::compareImportantModes;
+    }
+
     /**
      * Determines if this client is opped or not.
      *