[FEATURE] Fluid-based replacement for PageLayoutView

Provides a completely rewritten alternative to PageLayoutView
based on Fluid, and deprecates the old PageLayoutView. Adds
a feature flag TYPO3_CONF_VARS.SYS.features.fluidBasedPageModule
which can be used to switch back to the deprecated
PageLayoutView for installations which require this. The feature
flag is enabled by default in all new installations.

See included feature RST for more detailed information.

Releases: master
Resolves: #90348
Change-Id: Icf10b12130c238c63db74a608c67942ba912d307
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/63186


Tested-by: Kevin Appelt <kevin.appelt@icloud.com>
Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Manuel Selbach <manuel_selbach@yahoo.de>
Tested-by: Claus Due <claus@phpmind.net>
Reviewed-by: Kevin Appelt <kevin.appelt@icloud.com>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Manuel Selbach <manuel_selbach@yahoo.de>
Reviewed-b...