Add option to allow decoding CBOR floats into the Go int types.

[benluddy]

Description

The default behavior remains unchanged (CBOR floats can only be decoded into Go floats). By configuring the option, integral-valued CBOR floats can be decoded into the Go integer and unsigned integer types as long as the destination type is capable of faithfully representing their value.

PR Was Proposed and Welcomed in Currently Open Issue

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