fix for autoloader while user logged in and system is in maintenance

Conflicts:

	apps/files_encryption/appinfo/app.php
use legacyDecrypt to decrypt key file like the previous files_encryption
fix re-encrypt legacy files

Conflicts:

	apps/files_encryption/lib/util.php
fix legacy key in until test
normalize path to prevent following split to fail
cleanup unused method legacyKeyRecryptKeyfile