(PDB-1071) Add pagination to service query method

In order to support pagination in the service query method, have it
accept a map instead of the raw query structure.  The map should contain
a :query referring to the original query, alongside (optional)
:order-by, :offset, and :limit members.
it's pretty well covered in various spots, and this code is pretty transparent about passing the options to the existing machinery.  I don't think more is really required.