Add demoweb dump script and readme how to update demoweb DB.

Author: DOMjudge

dump_demoweb_db.sh

@@ -0,0 +1,18 @@
+#!/bin/sh
+# Script to dump the DOMjudge demo web DB to ~/demoweb/domjudge_
+# at:    https://www.domjudge.org/demoweb/
+
+set -e
+
+DBNAME='domjudge_demo'
+DUMPFILE=~/demoweb/${DBNAME}-$(date +%F).sql
+
+mysqldump $DBNAME | process-mysqldump > $DUMPFILE
+
+cat <<EOF
+
+Dumped demoweb DB in '$DUMPFILE'.
+
+Don't forget to diff the contents and update
+the ~/demoweb/domjudge_demo.sql symlink.
+EOF

update_demoweb_howto.txt

@@ -0,0 +1,8 @@
+To make updates to the demoweb DB (for example if the SQL structure changed):
+
+- run update_demoweb.sh to ensure the DB state is fresh
+- make the necessary changes
+- run dump_demoweb_db.sh to create a new file ~/demoweb/domjudge_demo-YYYY-MM-DD.sql
+- check that the new file differs from the previous dump in the expected way
+- update the symlink ~/demoweb/domjudge_demo.sql to point to the new dump
+- run update_demoweb.sh to test that the new file is loaded correctly