Implement high level helper functions for asynchronous APIs

[dspruell-s01]

The API server implements several asynchronous APIs that require users to submit job, poll for status, and finally fetch results. It would be logical and would help fulfill the purpose of the Python SDK as a high level client to expose helper methods that support handling these asynchronous backend jobs smoothly. The goal would be for a single call to handle necessary functionality:

1. Submit job
2. Poll for completion
3. Return results

Support should allow for some specification by user of things like poll period, maximum number of tries/timeout, etc. The higher level methods could then signal situations like timeouts and failures with exceptions or similar.

The outcome would be higher level support in the SDK that smooths out the user experience and enables simpler client code without the need to add in so much polling and retry logic, etc.

Similar ideas have been proposed in #3 and #32.