Log Message:
youtube-dl: Update to 20191022

Changes:
version 2019.10.22

Core
* [utils] Improve subtitles_filename (#22753)

Extractors
* [facebook] Bypass download rate limits (#21018)
+ [contv] Add support for contv.com
- [viewster] Remove extractor
* [xfileshare] Improve extractor (#17032, #17906, #18237, #18239)
    * Update the list of domains
    + Add support for aa-encoded video data
    * Improve jwplayer format extraction
    + Add support for Clappr sources
* [mangomolo] Fix video format extraction and add support for player URLs
* [audioboom] Improve metadata extraction
* [twitch] Update VOD URL matching (#22395, #22727)
- [mit] Remove support for video.mit.edu (#22403)
- [servingsys] Remove extractor (#22639)
* [dumpert] Fix extraction (#22428, #22564)
* [atresplayer] Fix extraction (#16277, #16716)