Ability to upload non-image files

Hi,
The ability to upload non-image files was missing, which rendered the "embed flash" button completely broken.
I've fixed views.py so that it wouldn't assume that the file is an image and also changed the galleriffic filebrowser to display nice file icons for non-image files.

Other minor issues I fixed along the way:
- Added i18n support
- Fixed filename localisation issues
- Fixed the gallery js to consider the image and viewport height when resizing images. (displaying very tall images was broken)