Reworked the image display page

This new version does not refresh the entire page all the time and only adds images that are new since the last pull. Those images are added to the top/front. They are shown as thumbnails (you can set their size in the script), linking to the full versions.

What is not supported:
* Old images (that are removed from the server) aren't automatically removed from the page.
* Images can not be inserted in between other images. All new images appear at the top/front of the list, even if their file names (their creation date) indicate otherwise.
But I'm guessing that's not a problem?

If you don't like the grid view, just comment out the float: left style.