--tweaks to get in sync with changed backend api; -- break accounting

[Linas Vepstas]

Log Message:
-----------
--tweaks to get in sync with changed backend api;
-- break accounting periods, for now

Tags:
----
backend-work-1

Modified Files:
--------------
    gnucash/src/backend/postgres:
        PostgresBackend.c
        book.c
        gncquery.c
        price.c
        putil.h