Summary: Patch from Thomas Berezansky providing an alternate implementation of Hard...

Summary: Patch from Thomas Berezansky providing an alternate implementation of Hard Due Dates.

Overview:
 * Moves hard due date configuration from the duration rule to the circ matrix
 * Implements backward-compatible API for circ scripts
 * Provides a stored procedure which updates hard due date values on demand

Further extension by Mike Rylander:
 * Provide a srfsh script and crontab.example entry to fire the stored procedure nightly
 * Expose stored procedure and add to the upgrade script

TODO: Create UIs for configuring hard due dates; integrate into version upgrade scripts

git-svn-id: svn://svn.open-ils.org/ILS/trunk@18396 dcc99617-32d9-48b4-a31d-7c20da2025e4