+#
+# MAIN ADMINISTRATIVE DATABASE UPDATE TOOL
+#
+# Usage:
+# ./update-master-info [-d RSYNCDESTDIR] [-O OCEAN ... | -a]
+#
+# Usual usages:
+#
+# After editing source-info.txt to add commodities, or
+# changing db-idempotent-update (eg to change the schema):
+# ./update-master-info -d ~ftp/users/ijackson/yarrg/
+# This will update everything except the ocean topologies.
+#
+# To take account of new islands, or to fix a mistake in
+# assigning island(s) to archipelago(es), or to add support
+# for a new ocean:
+# ./update-master-info -d ~ftp/users/ijackson/yarrg/ -O Midnight
+#
+# After a fix to a mistake on a YPPedia chart page, correcting
+# only inter-island-distances:
+# ./update-master-info -O Midnight
+#
+# After changing the algorithms for topology determination
+# or YPPedia scraping:
+# ./update-master-info -a
+# and check that nothing unexpected changes.
+#
+# To just make backups of the databases into the rsync directory:
+# ./update-master-info -b -d ~ftp/users/ijackson/yarrg/ -a
+# ./update-master-info -b -d ~ftp/users/ijackson/yarrg/ -O ...