[TASK] Update copyright year to 2013

Resolves: #46085
Releases: 6.1, 6.0, 4.7, 4.6, 4.5
Change-Id: I3e99389587ffc3808239bfa2da70670a07fa44be
Reviewed-on: https://review.typo3.org/18787
Reviewed-by: Ernesto Baschny
Tested-by: Ernesto Baschny