Add cirus-ci for freebsd CI about filesystem

[soroshsabz]

@Lastique I create PR for this, and I happy to review it :)

[Lastique]

My account is restricted by U.S. trade controls law, so Cirrus CI won't register for me, even for the free payment plan.

I won't be registering Cirrus CI, and any other service that discriminates users based on their country.

[soroshsabz]

@Lastique Thanks for attention to this issue, I was surprised that you see this message, I think this tyrannical rule (message) is only for Iranian and few and limited other countries ( I don't your country). but I think you got some misunderstanding, this message does not means Cirrus CI or other marketplace App and service is prohibited for you, this rule is enforced by GitHub and apply in User level not App level as I know ( Of course, I may have mistake). so I don't think Cirrus CI has any restriction or discriminates. so If you agree with me, please open this issue

thanks for attention :)

[Lastique]

This isn't just a GitHub rule, this restriction applies to any US-based company doing business with parties under US trade sanctions. For example, it applies to Google (Gmail, Youtube) as well. However, these companies still provide free (non-commercial) services to everyone. Cirrus CI, on the other hand, doesn't provide services even to non-commercial users. Maybe there's a technical limitation imposed by GitHub, I don't know, but the fact remains - users, myself included, are discriminated, which I find unacceptable.