Support handling of "unwrapped" POJOs

[cowtowncoder]

(note: copied from FasterXML/jackson-databind#271)

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For example :

class A { public String text = "text"; }
class B { public @JsonUnwrapped A a = new A(); }

would serialize as :

{"text":"text"}

and the schema would be :

{"type":"object","properties":{"a":{"type":"object","properties":{"text":{"type":"string"}}}}}

but, this is not consistent with the serialized form, the schema should be this :

{"type":"object","properties":{"text":{"type":"string"}}}

[cowtowncoder]

Ok: should all be fixed now, as per #61, thanks to @ciderale. Will be in 2.5.2 (and, if it gets released, 2.4.6).