[FEATURE] Add Data Processing to FLUIDTEMPLATE content object

The content object FLUIDTEMPLATE is extended with `dataProcessing`. With this
setting you can add full namespace class references, which can manipulate
the $data variable of the current rendered content object, like tt_content or
page, before assigning this variable to the view.

Change-Id: I757db37d86e1cf907de0116c3c63effc5270a3c1
Resolves: #66907
Releases: master
Reviewed-on: http://review.typo3.org/39519


Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Frans Saris <franssaris@gmail.com>
Tested-by: Frans Saris <franssaris@gmail.com>
Reviewed-by: Benjamin Mack <benni@typo3.org>
Tested-by: Benjamin Mack <benni@typo3.org>