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_misc_email_invitation.py

@@ -254,7 +254,7 @@ class InvitationsPlugin(object):
                     try:
                         yield self.host.plugins['XEP-0077'].registerNewAccount(jid_,
                                                                                password)
-                    except error.StanzaError as e:
+                    except error.StanzaError:
                         idx += 1
                     else:
                         break
@@ -321,7 +321,7 @@ class InvitationsPlugin(object):
             format_args['url'] = invite_url
 
             yield sat_email.sendEmail(
-                self.host,
+                self.host.memory.config,
                 [email] + emails_extra,
                 (kwargs.pop('message_subject', None) or DEFAULT_SUBJECT).format(
                     **format_args),
@@ -401,7 +401,7 @@ class InvitationsPlugin(object):
             C.PROF_KEY_NONE: don't filter invitations
         @return list(unicode): invitations uids
         """
-        invitations = yield list(self.invitations.items())
+        invitations = yield self.invitations.items()
         if profile != C.PROF_KEY_NONE:
             invitations = {id_:data for id_, data in invitations.items()
                            if data.get('profile') == profile}