[vultr] Support $2.50 / month IPV6 only instances

[sandlerben]

Is your feature request related to a problem? Please describe.

I would love to spend as little on hosting as possible :)

Describe the solution you'd like

Support deploying to the $2.50 / month IPV6 only instances. I believe these are just available for New York and Atlanta.

[ItsNayabSD]

Yes. Seems IPv6 only instances available for New York (NJ) and Atlanta. This is what I am getting when I try to configure one of these instances.

TASK [cloud-vultr : Upload the startup script] **********************************************************************************************************************************************************************************************
ok: [localhost]

TASK [cloud-vultr : Creating a server] ******************************************************************************************************************************************************************************************************
fatal: [localhost]: FAILED! => {"changed": false, "msg": "Could not find plans with VPSPLANID: 199"}

TASK [include_tasks] ************************************************************************************************************************************************************************************************************************
included: /home/nayab/algo/playbooks/rescue.yml for localhost

TASK [debug] ********************************************************************************************************************************************************************************************************************************
ok: [localhost] => {
    "fail_hint": [
        "Sorry, but something went wrong!",
        "Please check the troubleshooting guide.",
        "https://trailofbits.github.io/algo/troubleshooting.html"
    ]
}

TASK [Fail the installation] ****************************************************************************************************************************************************************************************************************
fatal: [localhost]: FAILED! => {"changed": false, "msg": "Failed as requested from task"}

PLAY RECAP **********************************************************************************************************************************************************************************************************************************
localhost                  : ok=36   changed=1    unreachable=0    failed=1    skipped=1    rescued=1    ignored=0