Bug 12443 - Initial re-factoring of buildQuery

This patch reduces three repeated code fragments into a single
internal subroutine, which is easier to read, has comments,
and should make it easier to refactor more buildQuery code
in the future.

_TEST PLAN_

Before applying

1) Run a bunch of different searches in the staff client and OPAC
in separate tabs

2) Apply the patch

3) Run the same searches again (maybe in yet more tabs) and notice
that the results are exactly the same.

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Same results, no errors.

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>
Bug 12443: (QA followup) Unit tests for _build_initial_query

This followup adds uint tests for the newly introduced function.
It is really basic, but covers all scenarios for the new function,
and will help us prevent regressions in future patches.

Regards
To+

Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>