Generate thumbnail and standard image on request, and use
http://github.com/mirumee/django-images for generating them. Also,
remove the CreatePin page as pin creation is going to be done
in JavaScript. Create UploadImage view for uploading images from
computer.

-e should be used only with repositories apparently

The previous commit uses url syntax from Django 1.5, which is incompatible with earlier versions. Bump the Django version
and use the stable/1.5.x git branch until it's officially released.