Add an "upload notes" field for uploaded images

[AetherUnbound]

We might receive some images from non-volunteer community members that might already have identified officers. We should add a mechanism for community members to attach notes to an uploaded image so that volunteers don't need to re-identify the images. This will likely require changing how the upload box looks in order to incorporate this. It will also likely require a new database field, and a modification to the classification page to showcase the notes alongside the image.