[TASK] Clean up phpDoc comments in t3lib classes

Clean up phpDoc comments for the following classes:

* t3lib/class.t3lib_userauth.php
* t3lib/class.t3lib_userauthgroup.php

Clean up provides:

* Provide correct parameter names in phpDoc
* Provide correct data types in phpDoc
* CGLify phpDoc (remove tabs)

Change-Id: I43687e094a75b05109e99fb0adb5164fa584b85f
Resolves: #37450
Releases: 6.0
Reviewed-on: http://review.typo3.org/11551
Reviewed-by: Oliver Klee
Reviewed-by: Philipp Gampe
Tested-by: Philipp Gampe
Reviewed-by: Tolleiv Nietsch
Tested-by: Tolleiv Nietsch