Optimization and bubble up ProducerResponseStatus

[jbeacham]

Optimization and bubble up ProducerResponseStatus to producer.Send method.

-Optimized DispatchSerializedData method in DefaultCallbackHandler.cs to use a single foreach method as opposed to multiple foreach statements.
-Added offset and partitionId to ProducerResponseStatus and bubbled it all the way to the producer.Send method. Kafka intended for this response to be available to the consumer for logging, health, etc.
-Added ShouldReturnOffset() unit test in DefaultCallbackHandlerTest.cs
-All Unit Tests passed

[msftclas]

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[msftclas]

@jbeacham, Thanks for signing the contribution license agreement so quickly! Actual humans will now validate the agreement and then evaluate the PR.

Thanks, MSBOT;

[jbeacham]

I do not have access to view the Details of the AppVeyor build fail reasons. Can somebody please let me know what they say.

[mhorstma]

Your PR failed to build because of a misconfigured appveyor build project that was a result of the name change of the github project. After this failed, I cleaned out the bad appveyor build and your PR should build fine now.

[jbeacham]

Awesome, thank you!