Update `add` method in AssetManager, put the model at the beginning

package.json

@@ -1,7 +1,7 @@
 {
   "name": "grapesjs",
   "description": "Free and Open Source Web Builder Framework",
-  "version": "0.9.43",
+  "version": "0.9.46",
   "author": "Artur Arseniev",
   "license": "BSD-3-Clause",
   "homepage": "http://grapesjs.com",

src/asset_manager/index.js

@@ -136,6 +136,12 @@ module.exports = () => {
      * }]);
      */
     add(asset, opts = {}) {
+
+      // Put the model at the beginning
+      if (typeof opts.at == 'undefined') {
+        opts.at = 0;
+      }
+
       return assets.add(asset, opts);
     },
 
@@ -308,6 +314,14 @@ module.exports = () => {
 
     //-------
 
+    AssetsView() {
+      return am;
+    },
+
+    FileUploader() {
+      return fu;
+    },
+
     postRender(editorView) {
       c.dropzone && fu.initDropzone(editorView);