[TASK] Update copyright year to 2013

Resolves: #46085
Releases: 6.1, 6.0, 4.7, 4.6, 4.5
Change-Id: I970078281d129be8ffef0bef128b23354ce59ddd
Reviewed-on: https://review.typo3.org/18785
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn