more areas to click/tap, no more unwatchable videos

album-grid:
- if using simply masonry image view, allow watching videos by opening them in a simple masonry iframe instead of doing nothing

album-sdscroll and album-masonry:
- always allow opening images in simply masonry image view by always showing magnifier
- if not using image.php show image/video in masonry iframe when clicking on thumbnail instead of doing nothing
- replaced simply masonry image view with masonry iframe as this supports videos
- disable simply masonry

isImagePhoto -> isPhoto
isImageVideo -> isVideo
getFilePath -> getPath

includes image.php and image-popup.php

happened especially when images/albums per page is big (e.g. 50)

API got changed with newer versions, would require some modifications

Add slash to slideshow links

Without a final slash, the URL is rewritten with a 301, which means
that the browser uses the new URL, but not with POST as before, but
with GET and therefore all parameters are missing.