[TASK] Update copyright year to 2013

Change-Id: I3067c2dd50cb7e75af35c5e29b801d3fc91d7bec
Resolves: #46356
Releases: 6.1
Reviewed-on: https://review.typo3.org/18970
Reviewed-by: Philipp Gampe
Tested-by: Philipp Gampe