jp: jp asyncio port:

/!\ this commit is huge. Jp is temporarily not working with `dbus` bridge /!\

This patch implements the port of jp to asyncio, so it is now correctly using the bridge
asynchronously, and it can be used with bridges like `pb`. This also simplify the code,
notably for things which were previously implemented with many callbacks (like pagination
with RSM).

During the process, some behaviours have been modified/fixed, in jp and backends, check
diff for details.

sat/plugins/plugin_adhoc_dbus.py

@@ -236,7 +236,7 @@ class AdHocDBus(object):
                 flags=flags,
             )
 
-        defer.returnValue((bus_name, methods))
+        defer.returnValue((str(bus_name), methods))
 
     def _addCommand(self, client, adhoc_name, bus_name, methods, allowed_jids=None,
                     allowed_groups=None, allowed_magics=None, forbidden_jids=None,