[BUGFIX] Add PHPDoc documentation and escape makeInstance

Add more PHP documentation for future improvements. Also
escape the backslashes in the makeInstance calls in the right
way.

Change-Id: I3bb4773174002dc8b9085112996273390fc86dd0
Reviewed-on: https://review.typo3.org/31032
Reviewed-by: Jo Hasenau
Tested-by: Jo Hasenau