smaller changes and fixes

- fix the cloudflare challenge result if the last decimal places
  are zero (JS`s toFixed() removes trailing zeroes)
- fix downloading of kissmanga chapter-pages hosted on blogspot
  (accessing blogspot with "kissmanga.com" as referrer yields a 401)
- disable certificate validation for 'mangahere' tests
- update flickr test result

gallery_dl/extractor/readcomiconline.py

@@ -89,8 +89,8 @@ class ReadcomiconlineIssueExtractor(ReadcomiconlineBase, ChapterExtractor):
             "language": "English",
         }
 
-    @staticmethod
-    def get_images(page):
+    def get_images(self, page):
+        self.session.headers["Referer"] = None
         return [
             (url, None)
             for url in text.extract_iter(