When running youtube-dl to get a filename, pass --no-playlist

Seems that youtube-dl --get-filename on a playlist lists all the filenames
for the playlist, which can take quite some time. The code already only
took the first name, so --no-playlist can speed it up a lot.

This commit was sponsored by Brett Eisenberg on Patreon.

Annex/YoutubeDl.hs

@@ -204,6 +204,7 @@ youtubeDlFileNameHtmlOnly' url uo
 			[ Param url
 			, Param "--get-filename"
 			, Param "--no-warnings"
+			, Param "--no-playlist"
 			]
 		(Nothing, Just o, Just e, pid) <- liftIO $ createProcess
 			(proc "youtube-dl" (toCommand opts))

CHANGELOG

@@ -3,6 +3,7 @@ git-annex (7.20181122) UNRELEASED; urgency=medium
   * Make bittorrent special remote work w/o btshowmetainfo installed
     when it was build with torrentparser.
     Thanks, Robert Schütz
+  * When running youtube-dl to get a filename, pass --no-playlist.
 
  -- Joey Hess <id@joeyh.name>  Tue, 27 Nov 2018 12:29:27 -0400