Adding eventListeners property to layer, control, and map. Setting this property at construction registers the given listeners based on event type key. r=elemoine (closes #1404)

git-svn-id: http://svn.openlayers.org/trunk/openlayers@6435 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Map.js

@@ -336,6 +336,15 @@ OpenLayers.Map = OpenLayers.Class({
      */
     panTween: 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: panMethod
      * {Function} The Easing function to be used for tweening.  Default is
@@ -408,6 +417,9 @@ OpenLayers.Map = OpenLayers.Class({
                                             this.EVENT_TYPES, 
                                             this.fallThrough);
         this.updateSize();
+        if(this.eventListeners instanceof Object) {
+            this.events.on(this.eventListeners);
+        }
  
         // update the map size and location before the map moves
         this.events.register("movestart", this, this.updateSize);