Fix broken cropping with upscale=False
remove unnecessary function call
Fix #304, fix AdminImageWidget rendering issue

This fixes the issue where AdminImageWidget would fail to render because
the file was deleted but the kvstore not updated.
Fix pep8 errors and warnings
Merge pull request #320 from mariocesar/issue304-fix-admin-widget

Fix #304, fix AdminImageWidget rendering issue
Merge branch 'pep8'

Conflicts:
	sorl/thumbnail/admin/current.py
Update changes list for version 12
Merge pull request #317 from gregplaysguitar/sorl_master

Fix broken cropping with upscale=False
fix pep8
Release version 12.1c
add test method that checks for files
add delete option to thumbnail clear