add checking exists and delete
rename parameter and add function generate_filename
Revert "rename parameter and add function generate_filename"

This reverts commit 7d7afd0e843f07262886b959c276415320bcec58.
check file name from backend
add method get_filename
start test
edit test
change import
move get_path(), and modify if statement
Raise value error on non-existant source image
Merge pull request #40 from SeiryuZ/master

Raise value error on non-existant source image
Gallery object should now raise ValueError if user tries to create
a thumbnail from an empty image field.
Merge pull request #36 from jessicarasidi/storage_exists_delete

add checking exists and delete
Merge branch 'master' into post-processors

Conflicts:
	thumbnails/files.py
Merge branch 'post-processors' of github.com:SeiryuZ/django-thumbnails into post-processors
Moved file operations to optimize_image method