[TASK] Mention the crowdfunding sponsors in the manual.

Change-Id: Ic95f99bc1dfa6374e7571fc847e3e05594d8a7c4
Reviewed-on: http://review.typo3.org/34900
Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Tested-by: Oliver Klee <typo3-coding@oliverklee.de>