Support having a "handle" field for the RetryOptions object

Related - https://github.com/Azure/azure-functions-durable-js/issues/329

In retriable DF APIs, dotnet users can add a "handle" field to their "RetryOptions" object. This allows them to provide custom logic to determine whether or not to shortcircuit a retriable operation such that the task is no longer attempted. This is difficult to do in the OOProc model, but we should investigate how to enable it.

Some of the relevant dotnet documentation is here: https://docs.microsoft.com/en-us/dotnet/api/microsoft.azure.webjobs.extensions.durabletask.retryoptions?view=azure-dotnet

Start by reviewing the RetryOptions API in this Python repository, related issue #329, and the linked .NET RetryOptions documentation. Determine a feasible OOProc-compatible design for a handle callback and define the expected short-circuit behavior; done means the supported approach and scope are agreed.

Written by the indexing model from the issue text.