Roll back changes in Schema.sql because of syntax errors.

The hard-coded references to the context name are necessary, but it is not legal
to reference a PL/SQL function in a column default clause, so the method
chosen fails with syntax errors. It will probably be necessary to write trigger
PL/SQL to do the required defaulting.
Create language-specific materialised views to optimise PSQ country selection screens.

18 materialised views for each of English and French.
Also some reorganisation of DDL across files.
Treat null origins as "Various".
Ensure PSQ views return special PSR names when available.

E.g. "Serbia (and Kosovo: S/RES/1244 (1999))" rather than just Serbia.
Implement new method of adapting the context name to each individual schema.

Hard-code the context name into the DDL rather than calling a function to return
it, but generate the hard-coded literal in SQL*Plus, at the beginning of the
Schema.sql script.

Remove comments from Schema.sql file to acknowledge that it is henceforth a
manually maintained file rather than being generated from Data Modeler.