Lee Hinman fd991f32f9 Refactor TransportShardBulkAction and add unit tests
This refactors the `TransportShardBulkAction` to split it appart and make it
unit-testable, and then it also adds unit tests that use these methods.

In particular, this makes `executeBulkItemRequest` shorter and more readable
2017-02-28 19:53:18 -07:00
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