[DOC][FEATURE] Content elements based on Fluid

Releases: master
Resolves: #68516
Related: #38732
Change-Id: Ic2d655e69d35d70863cc68f48a91e3f3e2df0ec5
Reviewed-on: https://review.typo3.org/41932


Reviewed-by: Martin Bless <m.bless@gmx.de>
Tested-by: Martin Bless <m.bless@gmx.de>
Reviewed-by: Josef Glatz <josef.glatz@typo3.org>
Tested-by: Josef Glatz <josef.glatz@typo3.org>
Reviewed-by: Daniel Goerz <ervaude@gmail.com>
Tested-by: Daniel Goerz <ervaude@gmail.com>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>