New feature: maintain control numbers (001, 003, 035) for MARC records

New feature: maintain control numbers (001, 003, 035) for MARC records

If a site wishes to maintain their control numbers and control number
identifiers in authority, bibliographic, and MFHD MARC records according
to the MARC21 specification, they will now be able to:

1. Enable the global flag 'cat.maintain_control_numbers' to turn on
control number maintenance. This is disabled by default, so no changes
will be made by the system until the flag is enabled.

2. (Optionally) Set the cat.marc_control_number_identifier OU setting
to override the control number identifier for records owned by that OU;
if this is not set, then the control number identifier defaults to the
OU shortname.

3. Set the owner field for the records that are to be controlled; otherwise
they will fall back to the global default which is currently hardcoded as
'EVRGRN'.

git-svn-id: svn://svn.open-ils.org/ILS/trunk@16899 dcc99617-32d9-48b4-a31d-7c20da2025e4