[Request] Add option to download user profile image, video watermark image, and extra video information

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[ ] Bug report (encountered problems with youtube-dl)
[ ] Site support request (request for adding support for a new site)
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If the purpose of this issue is a site support request please provide all kinds of example URLs support for which should be included (replace following example URLs by yours):

Single video: https://www.youtube.com/watch?v=BaW_jenozKc
Single video: https://youtu.be/BaW_jenozKc
Playlist: https://www.youtube.com/playlist?list=PL4lCao7KL_QFVb7Iudeipvc2BCavECqzc

Note that youtube-dl does not support sites dedicated to copyright infringement. In order for site support request to be accepted all provided example URLs should not violate any copyrights.

Description of your issue, suggested solution and other information

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Sample URL used throughout: https://www.youtube.com/watch?v=R93Vx8w64gQ

Hi there. Upfront I'd like to mention my English is not the greatest, it's not my natural language.

Anyway, I wanted youtube-dl to be able to download (on youtube):

-user profile image (so this) -video watermark (so this) -channel background (optional) (so this) -extra video information (so stuff like this)

Thank you for your time

ytdl-org / youtube-dl