Bug 12430: Add unit tests for C4::Search::buildQuery

Bug 12430: Add unit tests for C4::Search::buildQuery

This patch adds unit tests for buildQuery, especially focusing on
the use of the (rk=()) wrapper.

Note that the Net::Z3950::ZOOM library is used to test the queries
for CCL validity on top of the string matching used in the
got/expected comparisons.

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
JD amended patch: fix spelling connexion ==> connection

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>