Feincms3

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

- Made ``reverse_any`` mention all viewnames in the ``NoReverseMatch``
exception instead of bubbling the last viewname's exception.
- Added a ``RedirectMixin`` to ``feincms3.mixins`` for redirecting
pages to other pages or arbitrary URLs.
- Added a footgun plugin (raw HTML code).
- Reinstate Python 2 compatibility because Python 2 still seems to be in
wide use.

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

- Changed the implementation of the ``is_descendant_of`` template tag to
not depend on django-mptt_'s API anymore, and removed the
compatibility shims from ``AbstractPage``.
- Made the documentation build again and added some documentation for
the new ``feincms3.admin`` module.
- Made ``TreeAdmin.move_view`` run transactions on the correct database
in multi-DB setups.
- Removed the unused ``NoCommitException`` class.
- Fixed a crash in the ``MoveForm`` validation.
- Made ``AppsMiddleware`` work with Django's ``MIDDLEWARE`` setting.
- Made the ``{% menu %}`` template tag not depend on a ``page`` variable
in context.

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

- **BACKWARDS INCOMPATIBLE** Switched from django-mptt_ to
django-cte-forest_ which means that feincms3 is for the moment
PostgreSQL_-only. By switching we completely avoid the MPTT attribute
corruption which plagued projects for years. The `lft` attribute is
directly reusable as `position`, and should be renamed in a migration
instead of created from scratch to avoid losing the ordering of nodes
within a branch.
- Added a ``feincms3.admin.TreeAdmin`` which shows the tree hierarchy
and has facilities for moving nodes around.
- Avoided a deprecation warning on Django 1.10 regarding
``django.core.urlresolvers``.
- Started rolling releases using Travis CI's PyPI deployment provider.
- Made ``{% is_descendant_of %}`` return ``False`` if either of the
variables passed is no page instance instead of crashing.

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

- Dropped compatibility with Python 2.
- Fixed ``AbstractPage.save()`` to actually detect page moves correctly
again. Calling ``save()`` in a transaction was a bad idea because it
messed with MPTT's bookkeeping information. Depending on the
transaction isolation level going back to a clean slate *after*
``clean()`` proved much harder than expected.

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

- Added ``feincms3.apps.reverse_fallback`` to streamline reversing with
fallback values in case of crashes.
- The default template renderer context
(``TemplatePluginRenderer.register_template_renderer``) contains now the
plugin instance as ``plugin`` instead of nothing.
- Make django-mptt-nomagic_ a required dependency, by depending on the fact
that nomagic always calls ``Page.save()`` (django-mptt_ does not do that
when nodes are moved using ``TreeManager.node_move``, which is used in the
draggable mptt admin interface. Use a ``node_moved`` signal listener which
calls ``save()`` if the ``node_moved`` call includes a ``position`` keyword
argument if you can't switch to django-mptt-nomagic_ for some reason.

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

- Removed all dependencies from ``install_requires`` to make it easier
to replace individual items.
- Enabled the use of ``i18n_patterns`` in ``ROOT_URLCONF`` by importing
and adding the urlpatterns contained instead of ``include()``-ing the
module in ``apps_urlconf``.
- Modified the cleansing configuration to allow empty ``<a>`` tags
(mostly useful for internal anchors).
- Fixed crash when adding a page with a path that exists already (when
not using a statich path).