Photo Views: Count a mouseover as a view too

For video elements (animated GIFs), since the 'click' for lightbox modal
doesn't work, mouseover and play/pause count as views. This can unfairly
lead videos to climb as the most viewed images while pictures need a
click or a 'like' to count.

So, count images as viewed on their mouseover event as well.

web/templates/photo/gallery.html

@@ -945,7 +945,13 @@
 
                 // Log a view of this photo.
                 markImageViewed(photoID);
-            })
+            });
+
+            // Images: count a mouseover as a view to be on par with videos, otherwise
+            // videos climb to the top of the most viewed list too quickly.
+            node.addEventListener("mouseover", (e) => {
+                markImageViewed(photoID);
+            });
         });
     });
 </script>