Update scripts/xml2db.pl to use the new Scottish Parliament data

We only need to load the meeting-of-the-parliament section, since
we only need data after the parliament website changed - this was
before the terminology switched from "plenary" to "meeting of the
parliament".
Scotland: page and page_all should be distinct

This should fix the problem where we see "See this speech in context"
even on the full debate page.
Remove the warning about Scotland no longer being present
Make sure we don't overwrite the old Scottish Parliament data