Fixed imagecrop_field's max_filesize validation.  #896

Patched contrib module.  Patch here: http://drupal.org/node/1923934#comment-7164794

Gave slideshow slides a 4mb max.
Merge pull request #1988 from openscholar/896-image_filesize_validate

Fixed imagecrop_field's max_filesize validation.  #896
Looks Goood