Update tox.ini: drop tests for python 3.2
Update tox.ini: drop tests for python 3.2

from django.utils.module_loading import module_has_submodule

  File "/home/travis/build/infinityxxx/django-thumbnail-maker/.tox/py33-1.9/lib/python3.3/site-packages/django/utils/module_loading.py", line 67, in <module>

    from importlib.util import find_spec as importlib_find

ImportError: cannot import name find_spec


Seems that #`find_spec` is unsupported for Python 3.3
infinityxxx/django-thumbnail-maker,infinityxxx/django-thumbnail-maker,infinityxxx/django-thumbnail-maker