109.32.00

- Added `val Option.merge: 'a t -> 'a t -> f:('a -> 'a -> 'a) -> 'a t`.

- Added `val Validate.failf : ('a, unit, string, t) format4 -> 'a`.

- In `Validated.Make_binable`, made it possible to apply the validation function when un-bin-io-ing a value.

- Added `module Pooled_hashtbl` to `module type Hashable`.

  This is an alternative implementation to `Core.Hashtbl`.  It uses a
  standard linked list to resolve hash collisions, and `Pool` to manage
  the linked-list nodes.