[lio-py]: Add lio_dump.py updates for optparse
[lio-py]: Add lio_dump.py updates for optparse

This patch adds basic optparse functionality for lio_dump.py for
dumping to STDOUT (legacy operation), and now backup running config to
/etc/target/backup/

lio_dump.py --stdout is now called directly by tcm_dump.py --backup and
tcm_dump.py --overwrite usage.  Here are the help output:

usage: lio_dump [options]

options:
  -h, --help            show this help message and exit
  --s, --stdout         Dump running LIO-Target/ConfigFS syntax to STDOUT
  --t=DATE_TIME, --tofile=DATE_TIME
                        Backup running LIO-Target/ConfigFS syntax to
                        /etc/target/backup/lio_backup-<DATE_TIME>.sh

Signed-off-by: Nicholas A. Bellinger <978acd1567d5598152161fdf8bf3ca568f950c9b@linux-iscsi.org>

Datera/lio-utils,Datera/lio-utils,Datera/lio-utils,Datera/lio-utils