Select filter now has customizable "all" option (i.e. the first option labeled with '-')

I've provided means to customize the "all" option (i.e. the unconditionally added dash ('-') as first option to the selectbox). The _title_ (defaults to '-') as well as the _id_ (defaults to the empty string) should be customizable. Now, this can be achieved with **data-all-option-title** and **data-all-option-id**.

If `null` is needed for the *id* then provide the string `data-all-option-id="<null>"`.

Example:
```html
<td data-title="Status" filter="{'status': 'select'}" filter-data="[{title: 'published', id: 1}, {title: 'draft', id: 2}]" data-all-option-title="All" data-all-option-id="<null>">...</td>
```