Net/ddclient - Add Custom PATCH

[Hunv]

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Is your feature request related to a problem? Please describe.
I try to update a DNS entry at my DNS provider using a HTTP PATCH but recognized only GET, PUT and POST exists. My provider seems to use "udmedia" as a management system for the DNS API, so also other DNS providers may be affected. See https://hilfe.udmedia.de/domains/steht-eine-dns-api-zur-verfuegung/ at Creates/modifies/deletes RRsets present in the payload and their comments

Describe the solution you'd like
An additional property at the "Protocol" Box "Custom PATCH". Also an advice how/where to put the custom query as it is not obvious how/which field is to use to create a call with a body like this:

  {
  "id":"example.com.",
  "rrsets":[
    {
      "name":"foo.example.com.",
      "changetype":"REPLACE",
      "type":"A",
      "ttl":3600,
      "records":[ { "content":"127.0.0.2" } ] }
    ]
  }

Describe alternatives you've considered
A general "Custom" option where it is possible to choose the function in a seperate Combobox, but this may be harder to implement.

Additional context
See above.