/*
 * Load an Imlib2::Image from a file (throws exceptions).
 *
 * Examples:
 *   image = Imlib2::Image.load 'sample_file.png'
 *
 *   begin 
 *     image = Imlib2::Image.load 'sample_file.png'
 *   rescue Imlib2::FileError
 *     $stderr.puts 'Couldn't load file: ' + $!
 *   end
 *
 */
static VALUE image_load(VALUE klass, VALUE filename) {