Fixed packaging to include the templates

[kezabelle]

> pip install django-sniplates
Successfully installed django-sniplates Django
> cd lib/python2.7/site-packages/sniplates/
> tree .
.
├── __init__.py
├── models.py
└── templatetags
    ├── __init__.py
    └── sniplates.py

1 directory, 4 files

So yeah, according to the 0.3.1 tag the templates/sniplates/django.html file should be part of the release, but it wasn't.

The following patch fixes that. Used check-manifest (pip install) to generate the MANIFEST.in of what should definitely be in the sdist. To check it works:

• run setup.py build and run tree build
• run pip install wheel
• setup.py bdist_wheel
• rename the .whl file to .zip and unzip it, and then tree the directory extracted.

[sergei-maertens]

Maybe a good idea to add a test that should render the shipped template and use assertTemplateUsed, that way packaging is unit tested via tox.