New Tags to indicate the aspect ratio of the image

Posted under Tags

- The new tags could be just 3: "Landscape_(aspect_ratio)" (when image height < width) "Portrait_(aspect_ratio)" (when image height > width) or "Square_(aspect_ratio)" (when image height == width).
- Useful for searching images to set background for mobile (need Portrait images) or pc (need Landscape ones).
- Right now the existing tags "Landscape" and "Portrait" are for specific style of images, there are no tags to indicate the image's aspect ratio.