[bilibili] Switch to v2 playurl API

youtube_dl/extractor/bilibili.py

@@ -152,7 +152,7 @@ class BiliBiliIE(InfoExtractor):
             sign = hashlib.md5((payload + self._BILIBILI_KEY).encode('utf-8')).hexdigest()
 
             video_info = self._download_json(
-                'http://interface.bilibili.com/playurl?%s&sign=%s' % (payload, sign),
+                'http://interface.bilibili.com/v2/playurl?%s&sign=%s' % (payload, sign),
                 video_id, note='Downloading video info page',
                 headers=headers, fatal=num == len(RENDITIONS))