Feincms3

~~~~~~~~~~~~~~~~~~~~

The diff for this release is big, but there are almost no changes in
functionality.

- Minor documentation edits, added a form builder example app to the
documentation.
- Made ``reverse_fallback`` catch ``NoReverseMatch`` exceptions only,
and fixed a related test which didn't reverse anything at all.
- Switch to tox_ for building docs, code style checking and local test
running.
- Made the ``forms.Media`` CSS a list, not a set.

~~~~~~~~~~~~~~~~~~~~

- Slight improvements to ``TreeAdmin``'s alignment of box drawing characters.
- Allow overriding the outer namespace name used in ``feincms3.apps`` by
setting the ``LANGUAGE_CODES_NAMESPACE`` class attribute of the pages
class. The default value of ``language-codes`` has been changed to
``apps``. Also, the outer instance namespaces of apps are now of the
form ``<LANGUAGE_CODES_NAMESPACE>-<language_code>`` (example:
``apps-en`` for english), not only ``<language_code>``. This makes
namespace collisions less of a concern.

~~~~~~~~~~~~~~~~~~~~~~

- Minor documentation edits.
- Added the ``AncestorFilter`` for filtering the admin changelist by
ancestor. The default setting is to allow filtering by the first two
tree levels.
- Switched from feincms-cleanse_ to html-sanitizer_ which allows
configuring the allowed tags and attributes using a
``HTML_SANITIZERS`` setting.

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- Fixed the releasing-via-PyPI configuration.
- Removed strikethrough from our recommended rich text configuration,
since feincms-cleanse_ would remove the tag anyway.
- Made ``TemplatePluginRenderer.regions`` and the ``Regions`` class into
documented API.
- Made ``register_template_renderer``'s ``context`` argument default to
``default_context`` instead of ``None``, so please stop passing
``None`` and expecting the default context to work as before.
- Before adding Python 2 compatibility, a few methods and functions had
keyword-only arguments. Python 2-compatible keyword-only enforcement
has been added back to make it straightforward to transition back to
keyword-only arguments later.

~~~~~~~~~~~~~~~~~~~~

- Dropped the ``is_descendant_of`` template tag. It was probably never
used without ``include_self=True``, and this particular use case is
better covered by checking whether a given primary key is a member
of ``page.cte_path``.
- Dropped the ``menu`` template tag, and with it also the
``group_by_tree`` filter. Its arguments were interpreted according to
the long-gone django-mptt_ and it promoted bad database querying
patterns.
- Dropped the now-empty ``feincms3_pages`` template tag library.
- Added a default manager implementing ``active()`` to ``AbstractPage``.

~~~~~~~~~~~~~~~~~~~~

- Removed Django_ from ``install_requires`` so that updating
feincms3 without updating Django is easier.
- Allowed overriding the Page queryset used in ``page_for_app_request``
(for example for adding ``select_related``).
- Moved validation logic in varous model mixins from ``clean()`` to
``clean_fields(exclude)`` to be able to attach errors to individual
form fields (if they are available on the given form).
- Added Django 1.11 to the build matrix on Travis CI.
- Fixed an "interesting" bug where the ``TreeAdmin`` would crash with
an ``AttributeError`` if no query has been run on the model before.