Add settings to customize orchestration client timeouts (#427)

[anttix]

Summary of changes

• Introduce new settings to control orchestration client timeouts
• Define individual timeouts for client operations that are most often used from http triggered functions / endpoints
• Modify timeout bucketing not to align short timeouts which would be materially adjusted by the alignment

Key design choices

• New timeout fields use TimeSpan type. This does not align with existing PartitonStartupTimeoutMinutes field but does align with how timeouts are specified in AzureStorageOrchestrationServiceSettings
• Define separate timeouts for orchestration creation and message passing calls which are expected to be used most in latency sensitive paths such as http endpoints

Testing done

• Tested manually with an internal client application

Feedback requested

Please review the use of TimeSpan type and overall fit and finish.

[anttix]

@microsoft-github-policy-service agree company="Microsoft"

[sebastianburckhardt]

LGTM. Thanks for submitting this!