youtube-dl: 2018.02.08 -> 2018.02.22

Semi-automatic update. These checks were performed:

- built on NixOS
- ran `/nix/store/a520a1ddi4fyfyjmkqpf5kgmdy481mpf-youtube-dl-2018.02.22/bin/.youtube-dl-wrapped -h` got 0 exit code
- ran `/nix/store/a520a1ddi4fyfyjmkqpf5kgmdy481mpf-youtube-dl-2018.02.22/bin/.youtube-dl-wrapped --help` got 0 exit code
- ran `/nix/store/a520a1ddi4fyfyjmkqpf5kgmdy481mpf-youtube-dl-2018.02.22/bin/.youtube-dl-wrapped --version` and found version 2018.02.22
- ran `/nix/store/a520a1ddi4fyfyjmkqpf5kgmdy481mpf-youtube-dl-2018.02.22/bin/youtube-dl -h` got 0 exit code
- ran `/nix/store/a520a1ddi4fyfyjmkqpf5kgmdy481mpf-youtube-dl-2018.02.22/bin/youtube-dl --help` got 0 exit code
- ran `/nix/store/a520a1ddi4fyfyjmkqpf5kgmdy481mpf-youtube-dl-2018.02.22/bin/youtube-dl --version` and found version 2018.02.22
- found 2018.02.22 with grep in /nix/store/a520a1ddi4fyfyjmkqpf5kgmdy481mpf-youtube-dl-2018.02.22

cc "@bluescreen303 @phreedom @AndersonTorres @fuuzetsu @fpletz"