Merge branch 'upstream'

# Conflicts:
#	connect/migration_handler.py
#	connect/models/__init__.py
#	connect/models/event.py
#	connect/models/fulfillment.py
#	connect/models/tier_config.py
#	tests/test_migration_handler.py
#	tests/test_tier_config.py

Author: JaviCerveraIngram

connect/__init__.py

@@ -40,7 +40,6 @@ def __init__(self, config=None):
     'config',
     'exceptions',
     'logger',
-    'migration_handler',
     'models',
     'resources',
     'FulfillmentAutomation',

connect/migration_handler.py

@@ -99,3 +99,7 @@ def removed_items(self):
         return list(filter(
             lambda item: item.quantity == 0 and item.old_quantity > 0,
             self.asset.items))
+
+    def needs_migration(self, migration_key='migration_info'):
+        # type: (str) -> bool
+        return self.asset.get_param_by_id(migration_key) is not None