* Grab the IDs of all the image attachments in a gallery so we can get the URL of the next adjacent image in a gallery,
* or the first image (if we're looking at the last image in a gallery), or, in a gallery of one, just the link to that image file
*/
* Grab the IDs of all the image attachments in a gallery so we can get the URL of the next adjacent image in a gallery,
* or the first image (if we're looking at the last image in a gallery), or, in a gallery of one, just the link to that image file
*/