Download from utv.unistra.fr (PR #1271)

Squashed to a single commit to keep the file 'youtube-dl' unchanged and remove the revert commit.
Rename utv.py to unistra.py and extract more info

There are other sites that could be named utv, which would conflict if they are added
Credit Pierre Rudloff for JeuxVideoIE and UnistraIE
Merge remote-tracking branch 'upstream/master'