(IAC-1190) add ignore_foreign when purging firewallchains

[DavidS]

This stops firewallchains from purging rules that do not look
like rules the module puts into place. This capability can be used
to co-exist with other firewall management solutions on the same
machine.

Improved flow in the README around setting up purging, make it
a user decision to enable, and add a pointer to ignore_foreign.

[puppet-community-rangefinder]

firewallchain is a type

Breaking changes to this file MAY impact these 21 modules (near match):

• railsdog-awsfirewall
• intelliment-itlm
• jethrocarr-speedychains
• karume-openstack
• calmenergy-fail2ban
• thias-rhel
• fervid-secure_linux_cis
• openstack-tripleo
• tomkrieger-remediate_install
• mikegleasonjr-server
• treydock-perfsonar
• narasimhasv-openstack
• puppetlabs-openstack
• autostructure-secure_linux_cis
• echoes-echoes_firewall
• tomkrieger-security_baseline
• shearn89-toughen
• puppetfinland-packetfilter
• andrewkroh-base_firewall
• praekeltfoundation-docker_firewall
• glorpen-g_docker

This module is declared in 108 of 575 indexed public Puppetfiles.

---

These results were generated with Rangefinder, a tool that helps predict the downstream impact of breaking changes to elements used in Puppet modules. You can run this on the command line to get a full report.

Exact matches are those that we can positively identify via namespace and the declaring modules' metadata. Non-namespaced items, such as Puppet 3.x functions, will always be reported as near matches only.

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (main@bf238be). Click here to learn what that means.
The diff coverage is n/a.

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  Coverage        ?   81.18%           
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  Files           ?       11           
  Lines           ?     1669           
  Branches        ?        0           
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  Hits            ?     1355           
  Misses          ?      314           
  Partials        ?        0           

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[MikaelSmith]

This looks sufficient for our needs.