Provide clear warning message if users doesn't have Azurite running

If user has `useDevelopment=true` set but Azurite isn't running, provide a clear warning message when `func start` is run (something like "make sure you have Azurite running"). Right now, no message is provided and Storage throws an exception.

Start by tracing the `func start` path used when `useDevelopment=true`, then reproduce the case with Azurite not running. The work is done when `func start` provides a clear warning telling users to make sure Azurite is running instead of only exposing the Storage exception.

Written by the indexing model from the issue text.