core: move module handling out of dispatcher

Split module handling code from the dispatcher.
The new class for managing Modules is called SecNode.

* change logging to no longer need a reference to modobj
* modules get a reference to the secnode obj instead of the
  dispatcher
* intermediate usage fixes for frappy_psi/sea

Change-Id: Ifee4bb47aa7a4508bb4a47c9a5873b7e2d5faf67
Reviewed-on: https://forge.frm2.tum.de/review/c/secop/frappy/+/32249
Reviewed-by: Alexander Zaft <a.zaft@fz-juelich.de>
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>

test/test_persistent.py

@@ -30,6 +30,10 @@ from frappy.lib import generalConfig
 from frappy.persistent import PersistentParam, PersistentMixin
 
 
+class SecNodeStub:
+    pass
+
+
 class DispatcherStub:
     def announce_update(self, modulename, pname, pobj):
         pass
@@ -48,7 +52,8 @@ logger = LoggerStub()
 class ServerStub:
     def __init__(self, equipment_id):
         self.dispatcher = DispatcherStub()
-        self.dispatcher.equipment_id = equipment_id
+        self.secnode = SecNodeStub()
+        self.secnode.equipment_id = equipment_id
 
 
 class Mod(PersistentMixin, Module):