Ability to disable sorting for columns
Ability to disable sorting for columns

Ability to disable sorting for columns

Add option "orderable" to the columns. If you set it to false, the column will not be sorting.
```
$this->crud->addColumn([
       'label' => "Example",
       'name' => 'example',
       'orderable' => false,
]);
```

Also, I removed sorting for actions column.
Laravel-Backpack/crud,Laravel-Backpack/crud,Laravel-Backpack/crud,Laravel-Backpack/crud