plugin XEP-0384: Implementation of Automatic Trust Management:

- Implementation of Trust Messages (XEP-0434)
- Implementation of Automatic Trust Management (XEP-0450)
- Implementations directly as part of the OMEMO plugin, since omemo:2 is the only protocol supported by ATM at the moment
- Trust system selection updated to allow choice between manual trust with ATM and BTBV
- dev-requirements.txt updated to include additional requirements for the e2e tests

fix 376

sat/plugins/plugin_xep_0374.py

@@ -207,8 +207,6 @@ class XEP_0374:
         else:
             # I'm not sure why this check is required, this code is copied from XEP-0384
             if sender_jid.userhostJID() == client.jid.userhostJID():
-                # TODO: I've seen this cause an exception "builtins.KeyError: 'to'", seems
-                # like "to" isn't always set.
                 try:
                     feedback_jid = jid.JID(message_elt["to"])
                 except KeyError: