Gallery lists for items now adjust to the height of the item's image and text

Previously, items that appeared in gallery views - such as video and thought galleries - would be chopped short (vertically) to get them to fit into a grid. This meant that we weren't seeing all of the images and introduced other layout issues. I have now added code that positions gallery items appropriately while not cutting them short - so galleries now look better and display more information.

Let me know if you see anything that's broken!