Azure-functions-worker

- Added support for Entity Trigger (https://github.com/Azure/azure-functions-python-library/pull/68)
2. Add PYTHON_THREADPOOL_THREAD_COUNT app setting (744)
3. Adding support for debug logs in executed functions. (745)

- Fix an issue where EnqueuedTimeUtc is returning None in EventHub trigger.
- Fix an issue where Blob trigger throws an exception when the blob does not exist in storage account. Will return None instead.
2. Append /home/site/wwwroot to sys.path to support import statement without \_\_app\_\_ namespace prefix (726)

2. Fix an issue where worker fails to load failover **azure.functions** library when customer's code is not importing the library properly.
3. Add Python Durable Functions support [227](https://github.com/Azure/azure-functions-python-worker/issues/227)

1. Reduce Linux and macOS Python worker size by enabling manylinux2010 wheel in Python worker. (https://github.com/Azure/azure-functions-python-worker/pull/782)

1. Add support for Python 3.9 on Linux and macOS. Windows is currently under development as gRPC Wheel for Python 3.9 is missing. [751, 766, 775]
2. Fix an issue where PYTHON_THREADPOOL_THREAD_COUNT is not recognized in Linux Consumption SKU [774]
3. Reverting the support for debug logs in executed functions introduced in 745. [780]