This marks a major step towards centralizing some of the "spec" logic
and creating a single access point for them. Because `ImageSpecFields`
are just alternative interfaces for defining and registering specs,
they can be accessed and overridden in the same manner as other specs
(like those used by template tags): via the spec registry.
Somewhere along the line, a change got merged that stopped using the
receivers module. This re-integrates it and moves changes made to the
old receivers (static methods on ImageSpecField) to them.
This new feature gives the user more control over *when* their images
are validated. Image cache backends are now exclusively for controlling
the *how*. This means you won't have to write a lot of code when you
just want to change one or the other.
Signals are now connected without specifying the class and non-IK
models are filtered out in the receivers. This is necessary because of
a bug with how Django handles abstract models.
Closes#126
While this change means users can no longer specify their own filenames,
changing a property of a processor, for example, will now result in a
new image. This solves a lot of the previous invalidation issues.
* develop:
IKContentFile accepts format hint
Additional mimetype utils
Don't get extension of empty filename
Tell people to import fields from the models module
Refactored AutoConvert into prepare_image
Docstring for save_image
Kill PIL's chattiness; fixes#91
PIL bug workaround
Use StringIO instead of temp file
Extract reusable save_image function
Rename SpecFile and move it to utils
Extract suggest_extension util from generator
Woah, globals
Add SpecFile.__unicode__
SpecFile is based after django.core.files.base.ContentFile, which lacks a __unicode__
method. This leads to an AttributeError when SpecFile.__repr__ is called. This is
easily resolved by giving SpecFile a proper __unicode__ method.
