This modifies the `MultiResultDecoder` interface to accept an
`io.ReadCloser` so the `ResultIterator` can close the `io.Reader`
instead of doing it through a defer call. It then makes it so the
`Cancel()` method will close the reader or the reader will be
automatically closed when `More()` returns false.
In order to facilitate this change the query.PartitionKey
interface was changed to use the values.Value interface.
Additionally map was previously broken when it needed to repartition.
Tests have been added.
Nathaniel Cook
Jonathan A. Sternberg
Adam