Log Message:
Update net/youtube-dl to 2017.09.02

Changes:
2017.09.02
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Extractors
* [youtube] Force old layout for each webpage (#14068, #14072, #14074, #14076,
  #14077, #14079, #14082, #14083, #14094, #14095, #14096)
* [youtube] Fix upload date extraction (#14065)
+ [charlierose] Add support for episodes (#14062)
+ [bbccouk] Add support for w-prefixed ids (#14056)
* [googledrive] Extend URL regular expression (#9785)
+ [googledrive] Add support for source format (#14046)
* [pornhd] Fix extraction (#14005)

2017.08.27.1
------------
Extractors
* [youtube] Fix extraction with --youtube-skip-dash-manifest enabled (#14037)

2017.08.27
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Core
+ [extractor/common] Extract height and format id for HTML5 videos (#14034)
* [downloader/http] Rework HTTP downloader (#506, #809, #2849, #4240, #6023,
  #8625, #9483)
    * Simplify code and split into separate routines to facilitate maintaining
    * Make retry mechanism work on errors during actual download not only
      during connection establishment phase
    * Retry on ECONNRESET and ETIMEDOUT during reading data from network
    * Retry on content too short
    * Show error description on retry

Extractors
* [generic] Lower preference for extraction from LD-JSON
* [rai] Fix audio formats extraction (#14024)
* [youtube] Fix controversy videos extraction (#14027, #14029)
* [mixcloud] Fix extraction (#14015, #14020)

2017.08.23
----------
Core
+ [extractor/common] Introduce _parse_xml
* [extractor/common] Make HLS and DASH extraction in_parse_html5_media_entries
  non fatal (#13970)
* [utils] Fix unescapeHTML for misformed string like \ 
"&a"" (#13935)

Extractors
* [cbc:watch] Bypass geo restriction (#13993)
* [toutv] Relax DRM check (#13994)
+ [googledrive] Add support for subtitles (#13619, #13638)
* [pornhub] Relax uploader regular expression (#13906, #13975)
* [bandcamp:album] Extract track titles (#13962)
+ [bbccouk] Add support for events URLs (#13893)
+ [liveleak] Support multi-video pages (#6542)
+ [liveleak] Support another liveleak embedding pattern (#13336)
* [cda] Fix extraction (#13935)
+ [laola1tv] Add support for tv.ittf.com (#13965)
* [mixcloud] Fix extraction (#13958, #13974, #13980, #14003)