Issue #1976158 by Berdir | msonnabaum: Rename entity storage/list/form/render "controllers" to handlers.
Issue #2269003 by damiankloip, Berdir: Fixed Unnecessary high memory usage in EntityType::getKeys().
Issue #2119905 by damiankloip, tim.plunkett, Berdir: Provide @ConfigEntityType and @ContentEntityType to have better defaults.