os-ddclient - Add configuration to support FreeDNS Randomized Update Token

[rfc4711]

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Is your feature request related to a problem? Please describe. Add functionality to FreeDNS update instead of username/password to add the Randomized Update Token

Describe the solution you'd like A clear and concise description of what you want to happen. Randomized token updates protect the password on the account.

Describe alternatives you've considered n/a.