This builds on top of a fix in Django 1.6, and has a workaround for
Django 1.4 and 1.5. When the base class points to a model that no longer
exists, it will be silently dropped in the polymorphic queryset results.
This behavior is identical to iterating over results when the derived
table doesn't have the object anymore.
The reason polymorphic broke was because it couldn't find some managers
anymore in the inheritance tree. Django 1.5 removes these and replaces
them with an `AbstractManagerDescriptor`. This patch restores those objects
- by default, django_polymorphic's pretty printing of querysets/objects (via ShowField*) is not used anymore
- ShowField mixins now also show the annotations (after the regular fields, prepended by "Ann:")
- cleaned up implementation.
- added python2.4 compatibility. Contributed by Charles Leifer. Thanks!
- general reorganization of the code - there is no single polymorphic.py module anymore,
so d-p now needs to be installed as a regular Django app
- polymorphic.VERSION/get_version added
- version numbering started: V0.5 beta