Based on https://github.com/zendframework/zend-form/releases/tag/release-2.1.3 (commit 3bf44b7d8aa76c1f15f711a9d37070b1bfbc84b0 in this repo)

- 3714: Laminas\Stdlib\ArrayObject::offsetExists() returning by reference
  (https://github.com/zendframework/zf2/issues/3714)
- 3855: Fix zendframework/zend-form#3852
  (https://github.com/zendframework/zf2/issues/3855)
- 3856: Simple route case insensitive
  (https://github.com/zendframework/zf2/issues/3856)