Make some FK constraints on config.metabib_field.id deferrable

Signed-off-by: Dan Wells <dbw2@calvin.edu>
Signed-off-by: Lebbeous Fogle-Weekley <lebbeous@esilibrary.com>
Upgrade script for config.metabib_field sequence redo

[LFW: s/DROP FUNCTION/DROP FUNCTION IF EXISTS/]

Signed-off-by: Dan Wells <dbw2@calvin.edu>
Signed-off-by: Lebbeous Fogle-Weekley <lebbeous@esilibrary.com>
Stamping 0841: make space in config.metabib_field sequence

Signed-off-by: Dan Wells <dbw2@calvin.edu>
Adding 0842 due to 2_3 backport issues

A clean backport of 0841 was not possible due to partial schema
differences in the upgrade.  While we may have planned ahead better,
add a script just for 2_3 upgraders which ends up being a no-op for
2_4+

Signed-off-by: Dan Wells <dbw2@calvin.edu>
Signed-off-by: Remington Steed <rjs7@calvin.edu>