* [Multi-Asic] Forward SNMP requests destined to loopback IP, and coming in through the front panel interface
present in the network namespace, to SNMP agent running in the linux host.
* Updates based on comments
* Further updates in docker_image_ctl.j2 and caclmgrd
* Change the variable for net config file.
* Updated the comments in the code.
* No need to clean up the exising NAT rules if present, which could be created by some other process.
* Delete our rule first and add it back, to take care of caclmgrd restart.
Another benefit is that we delete only our rules, rather than earlier approach of "iptables -F" which cleans up all rules.
* Keeping the original logic to clean the NAT entries, to revist when NAT feature added in namespace.
* Missing updates to log_info call.