Multi select drop down with tree indentation

gistfile1.txt

<div class="control labelMove bottomSpace4">
                            <select
                                id="org_node"
                                name="orgNode"
                                class="chosen-select"
                                chosen="treeDropOptions"
                                required
                                ng-model="indicator.org_node_id">
                                <option ng-repeat="opt in treeDropOptions" ng-value="opt.id">
                                    {{Array(opt.lvl * 7).join("&nbsp;")}} {{opt.name}}
                                </option>
                            </select>
                            <label for="org_node">Org Node</label>
                        </div>
<script>
 $http.get("/org_nodes/org_tree.json").success(function (tree) {
                var array = [];
                $scope.Array = Array;
                Utils.treeToArray( tree, array);
                $scope.treeDropOptions = array;
            });
</script>