ContentElementGenerator\CacheManager should respect fileCreateMask and folderCreateMask
T3\Dce\Components\ContentElementGenerator\CacheManager (cache_dce/output_plugin.php) should respect settings
when creating cache files.
Right now it's not possible to make cache files e.g. have group writable file permissions, which is often useful for deployments.
GeneralUtility::fixPermissions after file creation would be enough.