CLI: Dumping internal data structures to files, not to debug output

CLI: Dumping internal data structures to files, not to debug output

All the 'dump something' CLI commands now have a new mandatory
argument -- name of the file where to dump the data. This allows
for more flexible dumping even for production deployments where
the debug output is by default off.

Also the dump commands are now restricted (they weren't before)
to assure that only the appropriate users can run these time consuming
commands.