New eventListeners APIProperty for OpenLayers.Tile.

Same behavior as Map.eventListeners or Layer.eventListeners.
New listeners can be registered using the options parameter:

new OpenLayers.Tile.Image(layer, position, bounds, null, size, {
  eventListeners: {
    loadstart: function(evt) {
      // ...
    },
    loadend: function(evt) {
      // ...
    }
  }
});

lib/OpenLayers/Tile.js

@@ -38,6 +38,15 @@ OpenLayers.Tile = OpenLayers.Class({
      */
     events: null,
 
+    /**
+     * APIProperty: eventListeners
+     * {Object} If set as an option at construction, the eventListeners
+     *     object will be registered with <OpenLayers.Events.on>.  Object
+     *     structure must be a listeners object as shown in the example for
+     *     the events.on method.
+     */
+    eventListeners: null,
+
     /**
      * Property: id 
      * {String} null
@@ -109,10 +118,13 @@ OpenLayers.Tile = OpenLayers.Class({
 
         //give the tile a unique id based on its BBOX.
         this.id = OpenLayers.Util.createUniqueID("Tile_");
-        
-        this.events = new OpenLayers.Events(this);
 
         OpenLayers.Util.extend(this, options);
+
+        this.events = new OpenLayers.Events(this);
+        if (this.eventListeners instanceof Object) {
+            this.events.on(this.eventListeners);
+        }
     },
 
     /**
@@ -139,7 +151,11 @@ OpenLayers.Tile = OpenLayers.Class({
         this.size = null;
         this.position = null;
         
+        if (this.eventListeners) {
+            this.events.un(this.eventListeners);
+        }
         this.events.destroy();
+        this.eventListeners = null;
         this.events = null;
     },