local storage for blog thumbnails without filer
Merge remote-tracking branch 'origin/master' into LUN-1483

Conflicts:
	cms_blogger/models.py
	cms_blogger/settings.py
working on removing old file if new file is uploaded
overwrite previous file
need to pass id to widget; done on frontend
upload url works
upload file, show its thumnail; needs work
add a single image, as opposed to filer where you can add many
add/delete image; BAD: image is deleted when saving form
image is no longer deleted
limit filename to 100 characters
merge with master
upload problem for large files

maybe request to server is reissued it server doesn't respond in time
verify that file is uploaded completely
merge with master
rename thumbnail_image to poster_image
poster_image admin interface looks similar to the mockups
fade credit/caption into existence for poster image
validate width and height
merge with master