Issue #2257477 by droplet: Fixed Wrong system.mail label in system.schema.yml.
Issue #2278507 by alexrayu: Fixed Apply word break to text in table cells.
Issue #2209049 by tstoeckler, lokapujya: Allow field schemas to contain unique keys.
Issue #2279217 by cs_shadow: Fixed Indentation error in \Drupal\editor\Form\EditorImageDialog.
Issue #2280383 by andypost: Fixed settings.local.php after new bootstrap.
Issue #2205185 by larowlan, hairqles, andypost, slashrsm: Split up ForumManager to create ForumIndexStorage.
Issue #1963760 by amitgoyal, fnuppy | valthebald: Fixed Make sure install.php gives accurate information if Drupal is already installed.