[CLEANUP] Rework/simplify copyright header and remove @package

Align some files with old copyright headers, mostly in extbase and
fluid sysext which were missed in Task #59535. Also remove some left
@package statements missed in Task #43019.

Resolves: #64689
Releases: master, 6.2
Change-Id: I9838c9be73cb3a310ef2572fcc3843ff53dbf724
Reviewed-on: http://review.typo3.org/36519


Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Reviewed-by: Mathias Schreiber <mathias.schreiber@wmdb.de>
Tested-by: Mathias Schreiber <mathias.schreiber@wmdb.de>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>