Allow azure functions to take in List[EventHubEvent] (#31)

* Allow azure functions to take in List[EventHubEvent]

* Only accept List[_eventhub.EventHubEvent]

Author: Hazhzeng

azure/functions/eventhub.py

@@ -11,7 +11,11 @@ class EventHubConverter(meta.InConverter, meta.OutConverter,
 
     @classmethod
     def check_input_type_annotation(cls, pytype: type) -> bool:
-        return issubclass(pytype, _eventhub.EventHubEvent)
+        return (
+            issubclass(pytype, _eventhub.EventHubEvent)
+            or (issubclass(pytype, typing.List)
+                and issubclass(pytype.__args__[0], _eventhub.EventHubEvent))
+        )
 
     @classmethod
     def check_output_type_annotation(cls, pytype) -> bool: