Adds support for Floating IP

The fallback does not get executed on 204 responses, as those are successful responses. Fallbacks are only executed for error response codes. If the service returns a 204, then the configured response parsers take place (usually the ParseJson in JSON based APIs), and they may return null if the response has no body (and a 0 content-length).

This said, I was not referring to this concrete API call, but how our APIs look like from the outside, in general. Users won't read the source code and won't read the annotations of the methods they invoke (they shouldn't have to, and shouldn't need to understand them).

From a user point of view, there's only a method with a name, input parameters and produced result, and that should be enough to predict and understand how the method behaves.