Bug 33974: (follow-up) Adapt the orders endpoint

Bug 33974: (follow-up) Adapt the orders endpoint

In order to reduce the technical debt carried on the orders controller,
and to highlight the decisions made on the prior patch, I adapted the
list() orders controller using the new tools in town.

The result is this endpoint can now embed bibio, without needing to have
a custom piece of code.

To test:
1. Apply this patch
2. Run:
   $ ktd --shell
  k$ prove t/db_dependent/api/v1/*.t
=> SUCCESS: Tests pass :-D

Signed-off-by: Sam Lau <samalau@gmail.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>