[gameone] Add new extractor gameone

Currently only usable for downloading tv episodes residing under
http://www.gameone.de/tv/
[gameone] Added explanation for usage of http://cdn.riptide-mtvn.com/
[gameone] Added extraction of description and fixed failing tests
[gameone] Simplified extraction of description
[gameone] Added extraction of age_limit
[gameone] Added timestamp extraction
[tenplay] Add new extractor
[gameone] Fix indentation and removed unused constants
Credit @irtusb for vimple (#3073)
Merge remote-tracking branch 'adammw/tenplay'
[tenplay] PEP8
Credit @adammw for tenplay (#2954)
Merge remote-tracking branch 'tobidope/gameone'
[gameone] Sort formats
Credit @tobidope for gameone (#2941)