TYPO3 11

See merge request !6

This reverts commit 4f889d20.

[TASK] Restructure index fluid template

See merge request !7

[FEATURE] Properly cache the youtube thumbnail and deliver that as a picture tag (heavy performance improvement)

Change the way the YouTube API is called to RequestFactory,
because we do not want to care manually what method of
fetching urls is available on the server.