[FEATURE] Allow fallback paths in FLUIDTEMPLATE

Resolves: #61361
Releases: master, 6.2
Change-Id: I676722936892f164ae147d7f9abcb602e734ae7d
Reviewed-on: http://review.typo3.org/34343
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Reviewed-by: Frans Saris <franssaris@gmail.com>
Tested-by: Frans Saris <franssaris@gmail.com>
Reviewed-by: Markus Klein <klein.t3@reelworx.at>
Tested-by: Markus Klein <klein.t3@reelworx.at>