[youtube] Add code for signature 92 (Closes #1060)

youtube_dl/extractor/youtube.py

@@ -195,6 +195,8 @@ class YoutubeIE(InfoExtractor):
             return s[36] + s[79:67:-1] + s[81] + s[66:40:-1] + s[33] + s[39:36:-1] + s[40] + s[35] + s[0] + s[67] + s[32:0:-1] + s[34]
         elif len(s) == 81:
             return s[6] + s[3:6] + s[33] + s[7:24] + s[0] + s[25:33] + s[2] + s[34:53] + s[24] + s[54:81]
+        elif len(s) == 92:
+            return s[25] + s[3:25] + s[0] + s[26:42] + s[79] + s[43:79] + s[91] + s[80:83];
 
         else:
             raise ExtractorError(u'Unable to decrypt signature, key length %d not supported; retrying might work' % (len(s)))