Upload image with cropper.js

Detailed description: 1. The cropsize should be locked in a square size. 2. When the cropped file is saved it shall be saved in 4 places with the following sizes: a. ../product_images/raw - the raw cropped file. b. ../product_images/large - a 1000x1000px variant of the picture c. ../product_images/medium - a 240x240px variant. d.../product_images/small - a 140x140px variant. 3. Mysqli should be used to communicate with the database 4. filename should be: {product:id}_{$product_name}_{date(Ymdhis)}.{format} and be clean from illegal char and spaces. 5. The result should be saved in the table product_images with columns: filename = $filename}, product_id = $product_id and primary image is a special case: If no other picture exists on the product the primary image should be set to 1 otherwise 0. 6. Under the form every picture shoud be shown as a thumbnail wwhere the user can click an image to make it the primary image (and set all other products for this product, only one file per products should be primary.)