109.44.00

- Implemented `Dequeue.iter` directly, instead of as a specialization
  of `fold`.

  Extended random tests to cover `iter`.
109.45.00

- Changed `Blang.bind` to short-circuit `And`, `Or`, and `If`
  expressions.

  For example if `bind t1 f ` false`, then `bind (and_ t1 t2) `
  false`, and will not evaluate `bind t2 f`.

- Renamed `Dequeue.get` as `get_opt`, and `get_exn` as `get`, to be
  consistent with other containers which don't use the `_exn` suffix
  for subscripting exceptions.
- Removed `Source_code_position.to_sexp_hum`, in favor of
  `sexp_of_t_hum`, which works smoothly with `with sexp`.
- Changed `Flat_queue_unit_tests` to run `Flat_queue.invariant`, which
  was mistakenly not being used.