Issue #2533800 by alexpott: Remove all unused use statements from core

core/includes/batch.inc

core/includes/bootstrap.inc

core/includes/common.inc

core/includes/entity.inc

core/includes/file.inc

core/includes/form.inc

core/includes/install.core.inc

core/includes/module.inc

core/includes/pager.inc

core/includes/schema.inc

core/includes/theme.inc

core/includes/update.inc

core/includes/utility.inc

core/lib/Drupal/Component/Gettext/PoMemoryWriter.php

core/lib/Drupal/Component/Gettext/PoMetadataInterface.php

core/lib/Drupal/Component/Gettext/PoReaderInterface.php

core/lib/Drupal/Component/Gettext/PoStreamReader.php

core/lib/Drupal/Component/Gettext/PoStreamWriter.php

core/lib/Drupal/Component/Gettext/PoWriterInterface.php

...pal/Component/Plugin/Exception/InvalidDecoratedMethod.php