Add a function acq.attribute_debits() to attribute debits to funding

Add a function acq.attribute_debits() to attribute debits to funding
source credits, and thereby to funding sources.

This version is a rewrite.  The original version didn't work in
PostgreSQL 8.2 because it used arrays of composite types.  This
new version uses temporary tables instead.

M    Open-ILS/src/sql/Pg/200.schema.acq.sql
M    Open-ILS/src/sql/Pg/002.schema.config.sql
A    Open-ILS/src/sql/Pg/upgrade/0149.schema.acq.attribute-debits.sql

git-svn-id: svn://svn.open-ils.org/ILS/trunk@15447 dcc99617-32d9-48b4-a31d-7c20da2025e4