Added service register and unregister events. Addresses BUKKIT-816

src/main/java/org/bukkit/event/server/ServiceUnregisterEvent.java

@@ -0,0 +1,23 @@
+package org.bukkit.event.server;
+
+import org.bukkit.event.HandlerList;
+import org.bukkit.plugin.RegisteredServiceProvider;
+
+/**
+ * This event is called when a service is unregistered.
+ */
+public class ServiceUnregisterEvent extends ServiceEvent {
+    private static final HandlerList handlers = new HandlerList();
+
+    public ServiceUnregisterEvent(RegisteredServiceProvider<?> serviceProvider) {
+        super(serviceProvider);
+    }
+
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+}