[CLEANUP] Add phpDoc to properties in ext:backend

Fixes some minor things on the go.

Resolves: #62669
Releases: master
Change-Id: Ida96d56d5f81ac3f1050958aa8ed821613a87e67
Reviewed-on: http://review.typo3.org/33767
Reviewed-by: Frank Nägler <typo3@naegler.net>
Tested-by: Frank Nägler <typo3@naegler.net>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
[TASK] Message usage in reports module and extensionmanager

Refactoring the reports module a bit to no longer use status
message HTML for rendering since this is a misuse.

Similar change in extension manager configuration of salted
passwords extension.

Resolves: #62614
Releases: master
Change-Id: I0b3e4e1dfed72441bb01abdb4ad35b7dc058a606
Reviewed-on: http://review.typo3.org/33703
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>