Log Message:
youtube-dl: Update net/youtube-dl to 20171228

Changes:
2017.12.28
----------
Extractors
+ [internazionale] Add support for internazionale.it (#14973)
* [playtvak] Relax video regular expression and make description optional
  (#15037)
+ [filmweb] Add support for filmweb.no (#8773, #10368)
+ [23video] Add support for 23video.com
+ [espn] Add support for fivethirtyeight.com (#6864)
+ [umg:de] Add support for universal-music.de (#11582, #11584)
+ [espn] Add support for espnfc and extract more formats (#8053)
* [youku] Update ccode (#14880)
+ [openload] Add support for oload.stream (#15070)
* [youku] Fix list extraction (#15065)

2017.12.23
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Core
* [extractor/common] Move X-Forwarded-For setup code into _request_webpage
+ [YoutubeDL] Add support for playlist_uploader and playlist_uploader_id in
  output template (#11427, #15018)
+ [extractor/common] Introduce uploader, uploader_id and uploader_url
  meta fields for playlists (#11427, #15018)
* [downloader/fragment] Encode filename of fragment being removed (#15020)
+ [utils] Add another date format pattern (#14999)

Extractors
+ [kaltura] Add another embed pattern for entry_id
+ [7plus] Add support for 7plus.com.au (#15043)
* [animeondemand] Relax login error regular expression
+ [shahid] Add support for show pages (#7401)
+ [youtube] Extract uploader, uploader_id and uploader_url for playlists
  (#11427, #15018)
* [afreecatv] Improve format extraction (#15019)
+ [cspan] Add support for audio only pages and catch page errors (#14995)
+ [mailru] Add support for embed URLs (#14904)
* [crunchyroll] Future-proof XML element checks (#15013)
* [cbslocal] Fix timestamp extraction (#14999, #15000)
* [discoverygo] Correct TTML subtitle extension
* [vk] Make view count optional (#14979)
* [disney] Skip Apple FairPlay formats (#14982)
* [voot] Fix format extraction (#14758)

2017.12.14
----------
Core
* [postprocessor/xattr] Clarify NO_SPACE message (#14970)
* [downloader/http] Return actual download result from real_download (#14971)

Extractors
+ [itv] Extract more subtitles and duration
* [itv] Improve extraction (#14944)
+ [byutv] Add support for geo restricted videos
* [byutv] Fix extraction (#14966, #14967)
+ [bbccouk] Fix extraction for 320k HLS streams
+ [toutv] Add support for special video URLs (#14179)
* [discovery] Fix free videos extraction (#14157, #14954)
* [tvnow] Fix extraction (#7831)
+ [nickelodeon:br] Add support for nickelodeon brazil websites (#14893)
* [nick] Improve extraction (#14876)
* [tbs] Fix extraction (#13658)