* github-elsensee/ticket/stenudd/8558-2:
[ticket/8558] Fix operator
[ticket/8558] Fix field length in ACP
[ticket/8558] Use only one variable and improve explain string
[ticket/8558] Add config in migrations and schema_data
[ticket/8558] Add display name in emails from board
Conflicts:
phpBB/includes/functions_messenger.php