[Azure] Add guidance for batch operations

[mikekistler]

There are some good and not-so-good patterns for implementing bulk operations. We should provide guidance on these.

[markweitzel]

Snip from email with @tg-msft

There are a lot of different approaches to batching across Azure. Some services like Storage use multipart/mixed. Others like Search and Text Analytics use collections of jobs/tasks. I think I’d even lump things like Metrics Advisor/Time Series Insights as a columnar form of batching. Some services like Tables offer transactional batching while most require the customer assume the batched requests will be executed in any order. Some batching responses are returned immediately while other batching APIs are LROs. Some batching responses are relatively small while others are pageable. Some batching APIs allow you to obtain usable partial results while others don’t produce anything until the entire job is complete. How partial success and errors are exposed in the REST API and surfaced to customers in client libraries also varies wildly.

[rysweet]

Here are these:

https://docs.aws.amazon.com/batch/latest/APIReference/Welcome.html

https://cloud.google.com/tasks/docs/reference/rest

[rysweet]

thinking about code flows that customers have today you could look at things like docusign, certain dynamics apis, adobe image processing workflows, nuance sdks, etc.