share api expanded by tags (#26583)

* share api expanded by tags

* Modified files_sharing JS Unit tests

* modified tests. renamed request parameter. refactoring

* Update Share20OCS.php

Added missing function description

* Update Helper.php

Added missing function description

* Update Helper.php

implicit boolean conversion to !empty()

* Update Share20OCSTest.php

Signed-off-by: Morris Jobke <hey@morrisjobke.de>