Update Youtube-DL to 2017.07.23
Changelog:
- [YoutubeDL] Improve default format specification
- [YoutubeDL] Do not override id, extractor and extractor_key for url_transparent entities
- [extractor/common] Fix playlist_from_matches
- [itv] Fix production id extraction
- [vidio] Make duration non fatal and fix typo
- [mtv] Skip missing video parts
- [sportbox:embed] Fix extraction
- [npo] Add support for npo3.nl URLs
- [dramafever] Remove video id from title
- [egghead:lesson] Add support for lessons
- [funnyordie] Extract more metadata
- [youku:show] Fix playlist extraction
- [dispeak] Recognize sevt subdomain
- [adn] Improve error reporting
- [crunchyroll] Relax series and season regex
- [spiegel:article] Add support for nexx iframe embeds
- [nexx:embed] Add support for iframe embeds
- [nexx] Improve JS embed extraction
- [pearvideo] Add support for pearvideo.com