Django-tables2

- Define and use `get_table_data` in `MultiTableMixin` [538](https://github.com/jieter/django-tables2/pull/538) by [vCra](https://github.com/vCra) (fixes [#528](https://github.com/jieter/django-tables2/issues/528))
- Added `{% export_url <format> %}` template tag.
- Allow passing a `TableData`-derived class to the data argument of the `Table` constructor, instead of a QuerySet or list of dicts.

- `BoundColumn.attrs` does not evaluate `current_value` as `bool` [536](https://github.com/jieter/django-tables2/pull/536) by [pachewise](https://github.com/pachewise) (fixes [#534](https://github.com/jieter/django-tables2/issues/534))
- Allow more flexible access to cell values (especially useful for django templates) (fixes [485](https://github.com/jieter/django-tables2/issues/485))

- Follow relations when detecting column type for fields in `Table.Meta.fields` (fixes [498](https://github.com/jieter/django-tables2/issues/498))
- Renamed `Table.Meta.template` to `template_name` (with deprecation warning for the former) [542](https://github.com/jieter/django-tables2/pull/524) (fixes [#520](https://github.com/jieter/django-tables2/issues/520))
- Added Czech translation [533](https://github.com/jieter/django-tables2/pull/533) by [OndraRehounek](https://github.com/OndraRehounek)
- Added `table_factory` [532](https://github.com/jieter/django-tables2/pull/532) by [ZuluPro](https://github.com/ZuluPro)

- Fix typo in setup.py for `extras_require`.

- Dropped support for Django 1.8, 1.9 and 1.10.
- Add `extra_context` argument to `TemplateColumn` [509](https://github.com/jieter/django-tables2/pull/509) by [ad-m](https://github.com/ad-m)
- Remove unnecessary cast of record to `str` [514](https://github.com/jieter/django-tables2/pull/514), fixes [#511](https://github.com/jieter/django-tables2/issues/511)
- Use `django.test.TestCase` for all tests, and remove dependency on pytest and reorganized some tests [515](https://github.com/jieter/django-tables2/pull/515)
- Remove traces of django-haystack tests from the tests, there were no actual tests.

This is the last version supporting Django 1.8, 1.9 and 1.10. Django 1.8 is only supported until April 2018, so consider upgrading to Django 1.11!

- Added `tf` dictionary to `Column.attrs` with default values for the footer, so footers now have `class` attribute by default [501](https://github.com/jieter/django-tables2/pull/501) by [mpasternak](https://github.com/mpasternak)