The function index in the head of core classes is not maintained
and not useful in the time of powerful IDE's anymore.

Change-Id: If4e327b4e78f3b6fb74a3011d8c2eb5090abe690
Resolves: #27985
Reviewed-on: http://review.typo3.org/3128
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn