Cleaned up bukkit event registration a bit and fixed 2 warnings.

src/main/java/com/sk89q/worldedit/bukkit/WorldEditPlugin.java

@@ -135,7 +135,9 @@ public class WorldEditPlugin extends JavaPlugin {
      * Register the events used by WorldEdit.
      */
     protected void registerEvents() {
+        @SuppressWarnings("unused")
         PlayerListener playerListener = new WorldEditPlayerListener(this);
+        @SuppressWarnings("unused")
         PlayerListener criticalPlayerListener = new WorldEditCriticalPlayerListener(this);
 
         // The permissions resolver has some hooks of its own
@@ -152,7 +154,7 @@ public class WorldEditPlugin extends JavaPlugin {
     public void registerEvent(String typeName, Listener listener, Priority priority) {
         try {
             Event.Type type = Event.Type.valueOf(typeName);
-            this.getServer().getPluginManager().registerEvent(type, listener, priority, this);
+            getServer().getPluginManager().registerEvent(type, listener, priority, this);
         } catch (IllegalArgumentException e) {
             logger.info("WorldEdit: Unable to register missing event type " + typeName);
         }