Merge pull request #158 from DrMeers/master

Fixes Issue #157
Fix broken link in README.rst.
Merge pull request #159 from bmihelac/patch-1

Fix broken link in README.rst.
fix #161 django<1.4 compatibility broken
Merge pull request #162 from stefanfoulis/feature/issue-161

Fix django <1.4 compatibility

Fixes #161.
Move test utilities outside of the tests dir

It's less confusing -- this way it doesn't look like it is a module
testing the easy_thumbnails utils (and if utils tests get added, they
can go here instead).
Make a way to avoid generating missing thumbnails

With a Thumbnailer instance, thumbnailer.generate = False or explicitly
via thumbnailer.get_thumbnail(..., generate=False) returns None rather
than generating thumbnails that don't exist already.

A new easy_thumbnails.signals.thumbnail_missed signal allows you to
catch these misses and deal with them separately (e.g. offload
generation to a queue / separate process).
Add a thumbnailer_passive filter

Allows for templates to use the new passive get_thumbnail method for
aliases.

Adds tests for this tag and the thumbnailer filter, which was also
missing tests.
Document the thumbnailer filters

Minimal documentation, but it's better than nothing.
1.1
Pass in file name to Thumbnailer when saving a field with "resize_source" option enabled.
Added test for saving ThumbnailerImageField with resize_options enabled.
Edited installation materials to match package

setup.py and PyPI expect you to pip install easy-thumbnails. The docs proper have this correct as well, but the readme is incorrect.
Merge pull request #171 from adamfast/master

Update README with current installation information
Fix error with widget and uploaded images.
Small fix
Merge pull request #178 from camilonova/patch-3

Minor documentation fix
Add test for widget and uploaded images.
Merge pull request #167 from selwin/master

Pass in file name to Thumbnailer when saving field with "resize_source" (issue #137)
Fixed deprecation warning

`django.utils.hashcompat` is deprecated as of Django 1.5. Use `hashlib` instead.