Manage uploaded photos

[quernd]

Photos uploaded by authorized users are stored in the database (and will be sent out randomly) but the photo ID is not logged and there is no way to manage photos.

It would be nice if authorized users could:

• query photos by ID
• delete photos

Possible extension (requires changes to the database structure):

• keep track of which user uploaded a photo

[quernd]

Also, users should be able to subscribe to new photos being uploaded.