Crop and resize an image to create a square image

Changes for 1.0

• First public release
• Gave up on using hashes to check images as each build of libgd seems to use a different value from copyResampled.
• Instead we now generate the images on the fly meaning no big payloads to download.
• The checks are for initial size, upscaling and downscaling.
• Makefile.PL contains META_MERGE section