Merge branch '8.x' of git.drupal.org:project/drupal into 8.x

MAINTAINERS.txt

includes/common.inc

includes/file.inc

modules/field/field.api.php

modules/field/field.form.inc

modules/field/field.module

modules/field/tests/field.test

modules/field_ui/field_ui.admin.inc

modules/forum/forum-list.tpl.php

modules/forum/forum-rtl.css

modules/forum/forum.css

modules/forum/forum.install

modules/forum/forum.module

modules/forum/forum.test

modules/poll/poll.module

modules/poll/poll.test

modules/simpletest/tests/common_test.module

modules/simpletest/tests/common_test_cron_helper.info

modules/simpletest/tests/common_test_cron_helper.module

modules/system/system.admin.inc