Requests for comment/image and oldimage tables

There's no auto-incrementing primary key for, and no primary key at all for. This should be changed so we can add an imgids parameter to prop=imageinfo, rather than having to use timestamps. Also, it will eliminate the need to use a timestamp kludge in.

Add img_id, oi_id, and oi_img_id
When a new version of a file is uploaded, set oi_img_id to the file's former img_id.
 * img_id: Primary key
 * oi_id: Primary key
 * oi_img_id: The value of img_id before the version was moved from image to oldimage

Probably easier to code since it's a less drastic change
 * Advantages

Add img_id, img_latest, oi_id, and oi_img
img will be like the table, and oldimage will be like the  table.
 * img_id: Primary key
 * img_latest: oi_id of the current version of an image (similar to )
 * oi_id: Primary key
 * oi_img: img_id of the image this version corresponds to (similar to )

Eliminates the need to potentially check two tables (image and oldimage) if we already know the oi_id.
 * Advantages

Should we change the table names, and call them "image" and "imageversion" or something?
 * Questions