Merge pull request #108 from efedorov-dart/master

Fix threading error leading to boto3 S3 failures

garcon/activity.py

@@ -537,12 +537,19 @@ def __init__(self, flow, activities=None):
     def run(self):
         """Run the activities.
         """
-
+        threads = []
         for activity in self.activities:
             if (self.worker_activities and
                     activity.name not in self.worker_activities):
                 continue
-            threading.Thread(target=worker_runner, args=(activity,)).start()
+            thread = threading.Thread(
+                target=worker_runner,
+                args=(activity,))
+            thread.start()
+            threads.append(thread)
+
+        for thread in threads:
+            thread.join()
 
 
 class ActivityState: