Merge remote-tracking branch 'heyrocker/8.x-file-config' into 8.x

core/includes/bootstrap.inc

core/includes/common.inc

core/includes/config.inc

core/includes/file.inc

core/includes/form.inc

core/includes/install.core.inc

core/includes/install.inc

core/includes/language.inc

core/includes/module.inc

core/lib/Drupal/Core/Cache/DatabaseBackend.php

core/lib/Drupal/Core/Config/ConfigException.php

core/lib/Drupal/Core/Config/ConfigFileStorageException.php

...lib/Drupal/Core/Config/ConfigFileStorageReadException.php

...rupal/Core/Config/ConfigFileStorageSignatureException.php

core/lib/Drupal/Core/Config/DrupalConfig.php

core/lib/Drupal/Core/Config/DrupalConfigVerifiedStorage.php

...upal/Core/Config/DrupalConfigVerifiedStorageInterface.php

core/lib/Drupal/Core/Config/DrupalVerifiedStorageSQL.php

core/lib/Drupal/Core/Config/SignedFileStorage.php

core/modules/block/config/block.performance.xml