Removed __traits_version__ from json files

Created by: jjenthought

The workflow is a dictionary which contains lists of dictionaries, so only the traits_version keys in the top level dict were being removed. This changed the function so it should do it recursively. It seems fine but the only test is a on a single hardcoded example at the minute. Refs. issue https://github.com/force-h2020/force-bdss/issues/134

Fixes #134 (closed)

force_bdss/io/workflow_writer.py

 import json
 from traits.api import HasStrictTraits
-from collections import Iterable
 
 
 class WorkflowWriter(HasStrictTraits):
@@ -108,7 +107,7 @@ def pop_recursive(dictionary, remove_key):
     except KeyError:
         pass
 
-    for key,value in dictionary.items():
+    for key, value in dictionary.items():
         # If remove_key is in the dict, remove it
         if isinstance(value, dict):
             pop_recursive(value, remove_key)