location-importer.in: track original countries as well

location-importer.in: track original countries as well

This helps us to determine how many network objects have more than one
country set, and what their original country code set looked like.

The third version of this patch uses ALTER TABLE to add the column for
original countries, preventing existing SQL setups from breaking, and is
correctly based against the current "master" branch.

Signed-off-by: Peter Müller <peter.mueller@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>