code: def images(self, type):
          
          images = []
  
          res = yield from self.http_query("GET", "/{}/images".format(type), timeout=None)
          images = res.json
  
          try:
              if type in ["qemu", "dynamips", "iou"]:
                  for local_image in list_images(type):
                      if local_image['filename'] not in [i['filename'] for i in images]:
                          images.append(local_image)
                  images = sorted(images, key=itemgetter('filename'))
              else:
                  images = sorted(images, key=itemgetter('image'))
          except OSError as e:
              raise ComputeError("Can't list images: {}".format(str(e)))
          return images
docs: Return the list of images available for this type on controller
          and on the compute node.