Some basic test support

##make test##

Magic.

I see three failures locally:


```
======================================================================
FAIL: test_formset_layout (crispy_forms.tests.tests.TestFormLayout)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/dcramer/Development/django-crispy-forms/crispy_forms/tests/tests.py", line 935, in test_formset_layout
    ), 1)
AssertionError: 0 != 1

======================================================================
FAIL: test_modelformset_layout (crispy_forms.tests.tests.TestFormLayout)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/dcramer/Development/django-crispy-forms/crispy_forms/tests/tests.py", line 988, in test_modelformset_layout
    ), 1)
AssertionError: 0 != 1

----------------------------------------------------------------------
```

The third being an undefined template variable (inline_class) which gets hit in as_crispy_field