Distinguish empty_forms with inline formsets

When looping through forms within an inline–formset, it currently looks like this:

```
{% for inline_form in formset %}
{% endfor %}
```

That does not allow to separate between forms and empty_forms (which is needed if you want to hide the empty_form without using hacks). We currently use something like {% if forloop.last %} ... add container and hide contents ... {% endfor %} which obviously is not a nice solution.

Therefor, I propose this:

```
{% for inline_form in formset.forms %}
{% endfor %}
{{ formset.empty_forms }}
```