FluentIterable serialization doens't work for Bean Properties

In the depths of `BeanPropertyWriter`, the `JavaType` for the property [is constructed](https://github.com/FasterXML/jackson-databind/blob/2c67dce1784428cdb7a5a7a4079d1581b8ec90eb/src/main/java/com/fasterxml/jackson/databind/ser/BeanPropertyWriter.java#L703), but Type Modifiers don't get called on it, so the Type Modifier in this module doesn't help.

This fix explicitly handles the issue by using StdDelegatingDeserializer, which looks up the delegate deserializer using the static type of the delegate.

FWIW, I'd have rather just located and returned and instance of `IterableSerializer`, but there doesn't seem to be a clean way to do that in `Serializers#findSerializer`.