Fixes fragment import.

The fragment specification key was missing, thereby causing the fragment import to merge non-compatible structures. We now add the missing key.

tinytroupe/agent/tiny_person.py

@@ -265,7 +265,7 @@ def import_fragment(self, path):
 
         # check the type is "Fragment" and that there's also a "persona" key
         if fragment.get("type", None) == "Fragment" and fragment.get("persona", None) is not None:
-            self.include_persona_definitions(fragment)
+            self.include_persona_definitions(fragment["persona"])
         else:
             raise ValueError("The imported JSON file must be a valid fragment of a persona configuration.")
 
@@ -1373,4 +1373,4 @@ def clear_agents():
         """
         Clears the global list of agents.
         """
-        TinyPerson.all_agents = {}        
+        TinyPerson.all_agents = {}