Support the culture attribute in the Bing Layer.

p=dcabasson, r=me (closes http://trac.osgeo.org/openlayers/ticket/3598)

lib/OpenLayers/Layer/Bing.js

@@ -67,6 +67,13 @@ OpenLayers.Layer.Bing = OpenLayers.Class(OpenLayers.Layer.XYZ, {
      */
     type: "Road",
     
+    /**
+     * APIProperty: culture
+     * {String} The culture identifier.  See http://msdn.microsoft.com/en-us/library/ff701709.aspx
+     * for the definition and the possible values.  Default is "en-US".
+     */
+    culture: "en-US",
+    
     /**
      * APIProperty: metadataParams
      * {Object} Optional url parameters for the Get Imagery Metadata request
@@ -155,6 +162,7 @@ OpenLayers.Layer.Bing = OpenLayers.Class(OpenLayers.Layer.XYZ, {
     initLayer: function() {
         var res = this.metadata.resourceSets[0].resources[0];
         var url = res.imageUrl.replace("{quadkey}", "${quadkey}");
+        url = url.replace("{culture}", this.culture);
         this.url = [];
         for (var i=0; i<res.imageUrlSubdomains.length; ++i) {
             this.url.push(url.replace("{subdomain}", res.imageUrlSubdomains[i]));