make the images relative to the content rather than to the assets

check 9780596800611 for example

safaribooks.py

@@ -553,7 +553,7 @@ def get_book_chapters(self, page=1):
  self.display.exit("API: unable to retrieve book chapters.")
 
  response = response.json()
-
+ 
  if not isinstance(response, dict) or len(response.keys()) == 1:
  self.display.exit(self.display.api_error(response))
 
@@ -814,7 +814,7 @@ def get(self):
 
  # Images
  if "images" in next_chapter and len(next_chapter["images"]):
- self.images.extend(urljoin(next_chapter['asset_base_url'], img_url)
+ self.images.extend(urljoin(next_chapter['content'], img_url)
  for img_url in next_chapter['images'])
 
  # Stylesheets
@@ -863,6 +863,7 @@ def _thread_download_css(self, url):
  self.css_done_queue.put(1)
  self.display.state(len(self.css), self.css_done_queue.qsize())
 
+
  def _thread_download_images(self, url):
  image_name = url.split("/")[-1]
  image_path = os.path.join(self.images_path, image_name)