[vbox7] Don't set the extension to 'flv' (fixes #3836)
[anysex] Fix extraction
[extremetube] Fix extraction
[sport5] Add new extractor
Merge branch 'sport5' of https://github.com/lenaten/youtube-dl into lenaten-sport5
[YoutubeDL] Expect all kind of strings in urlopen

Now it doesn't fail if req is python2's str
[sport5] Capture error message and improve
Merge branch 'lenaten-sport5'
[sport5] Keep alphanumeric order
[YoutubeDL] Fix string check for python3