added script for ipmitool chassis status metrics

[wtip]

Example output of metrics below:

# HELP node_ipmi_chassis_fault Chassis Fault sensor reading from ipmitool
# TYPE node_ipmi_chassis_fault gauge
node_ipmi_chassis_fault{sensor="Drive Fault"} 0.000000
node_ipmi_chassis_fault{sensor="Power Control Fault"} 0.000000
node_ipmi_chassis_fault{sensor="Main Power Fault"} 0.000000
node_ipmi_chassis_fault{sensor="Cooling/Fan Fault"} 0.000000

On Dell poweredge servers I've only seen this trigger the drive fault sensor

[SuperQ]

Maybe better to add this to the ipmi_exporter.

[candlerb]

I have started using this chassis script - it's useful, thank you, and I'd like it to be included in this repository.

These ipmi scripts avoid having to run and scrape another service. Also generating textfile-collector output from cron avoids any issue around running ipmi_exporter as root or with sudo privileges.