[zdf] Add support for channels
[youtube] Fix imports
[utils] Add "yesterday" as a date keyword
[BehindKink] Update  URL extraction
[BehindKink] Replace test

Old one is not accessible anymore
Merge pull request #4440 from 5moufl/behindkink-fix

[BehindKink] update
[behindkink] Simplify
[behindkink] Remove superfluous whitespace
Merge branch 'master' of github.com:rg3/youtube-dl
[ntv] Rename `flash_ver` to `flash_version` in the format dict

RTMP downloader uses `flash_version`
[youtube] The case that 'url_encoded_fmt_stream_map' or 'adaptive_fmts' is the empty string is handled accordingly (fixes #4431)
[tvplay] Don't raise an exception if `is_geo_blocked` is True

Videos which return `is_geo_blocked' to be True can actually be downloaded from
the country to which the video is restricted
Merge branch 'master' of github.com:rg3/youtube-dl
[youtube] Add test case for #4431
Merge remote-tracking branch 'akretz/youtube_fix'
[youtube] Make category optional (#4442)
[youtube] Do not warn if DASH manifest is missing (#4442)
[youtube] Amend test
Merge remote-tracking branch 'akretz/master'
[zdf:channel] Simplify (#4427)