Development Team/Presence Service Removal

Some notes follow about how we can replace the implementation of the signals and methods in the Presence Service by another that uses more fully the telepathy framework and is stateless.

@dbus.service.signal(PRESENCE_INTERFACE, signature="o")
def ActivityAppeared(self, activity):
    pass

@dbus.service.signal(PRESENCE_INTERFACE, signature="o")
def ActivityDisappeared(self, activity):
    pass

@dbus.service.signal(PRESENCE_INTERFACE, signature="o")
def BuddyAppeared(self, buddy):
    pass

@dbus.service.signal(PRESENCE_INTERFACE, signature="o")
def BuddyDisappeared(self, buddy):
    pass

@dbus.service.signal(PRESENCE_INTERFACE, signature="oos")
def ActivityInvitation(self, activity, buddy, message):
    pass

@dbus.service.signal(PRESENCE_INTERFACE, signature="soos")
def PrivateInvitation(self, bus_name, connection, channel, chan_type):
    pass

@dbus.service.method(PRESENCE_INTERFACE, in_signature="",
                        out_signature="ao")
def GetActivities(self):
    pass

@dbus.service.method(PRESENCE_INTERFACE, in_signature="s",
                        out_signature="o")
def GetActivityById(self, actid):
    pass

@dbus.service.method(PRESENCE_INTERFACE, in_signature="",
                        out_signature="ao")
def GetBuddies(self):
    pass

@dbus.service.method(PRESENCE_INTERFACE, in_signature="ay", out_signature="o",
                        byte_arrays=True)
def GetBuddyByPublicKey(self, key):
    pass

@dbus.service.method(PRESENCE_INTERFACE, in_signature="sou",
                        out_signature="o")
def GetBuddyByTelepathyHandle(self, tp_conn_name, tp_conn_path, handle):
    pass

@dbus.service.method(PRESENCE_INTERFACE, in_signature="", out_signature="o")
def GetOwner(self):
    pass

@dbus.service.method(PRESENCE_INTERFACE, in_signature="", out_signature="so")
def GetPreferredConnection(self):
    pass

@dbus.service.method(PRESENCE_INTERFACE, in_signature="sssa{sv}",
        out_signature="o", async_callbacks=("async_cb", "async_err_cb"),
        sender_keyword="sender")
def ShareActivity(self, actid, atype, name, properties, async_cb,
                    async_err_cb, sender):
    pass

@dbus.service.method(PRESENCE_INTERFACE, in_signature="as", out_signature="")
def SyncFriends(self, keys):
    pass

@dbus.service.method(PRESENCE_INTERFACE, in_signature="", out_signature="")
def RestartServerConnection(self):
    pass