Issue1050786878 ods relationship code

Adding ODS custom group+field + table @ck434 @jab1012 Worth checking through , there's 1 line I'm unclear on whether its best practice (401 in upgrader.php) which seems to work fine, but I'm wondering if there's a better alternative for inputting the characters that show up in the extends_entity_column_value field in the custom group table that looks cleaner.