Construct Message from ArraySegment when sending to Queue

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In the current version of the library the Message object is constructed from a byte[] or Body can be set from a byte[]. In our case, messages are sourcing from a Socket where 4k buffers are read and reused from a pool. We want to construct Message objects to be sent to the Queue from ArraySegments spanning subsets of the 4k buffers. The API does not currently support such a pattern which forces us to allocate buffers and copy data which adds overhead and GC pressure. In high-performance, high-throughput situations, this becomes a significant performance hit.