v_* urls are individual videos, while a_* urls are playlists, which are not supported yet.
See the comments in #5849
For example, https://vid.me/Wmur contains more information than https://vid.me/e/Wmur
`og:description` does not contain actual description anymore.
[iprima] Update
[youtube] Construct a playlist URL in case the page is missing one
This fixes jumping from user/channel -> playlist for some users like https://www.youtube.com/user/BitcoinFoundation This also removes the superfluous log message "add --no-playlist to just download video VIDEOID" when downloading a user/channel.