improve handling of module init methods

- complain when super call is omitted (this is a common programming
  error in Mixins)
- redesign waiting mechanism for startup

+ rename MultiEvent method 'setfunc' to 'get_trigger'

Change-Id: Ica27a75597321f2571a604a7a55448cffb1bec5e
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/27369
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>
Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>

secop_mlz/entangle.py

@@ -376,8 +376,8 @@ class AnalogInput(PyTangoDevice, Readable):
     The AnalogInput handles all devices only delivering an analogue value.
     """
 
-    def startModule(self, started_callback):
-        super().startModule(started_callback)
+    def startModule(self, start_events):
+        super().startModule(start_events)
         try:
             # query unit from tango and update value property
             attrInfo = self._dev.attribute_query('value')
@@ -454,8 +454,8 @@ class AnalogOutput(PyTangoDevice, Drivable):
         self._history = []  # will keep (timestamp, value) tuple
         self._timeout = None  # keeps the time at which we will timeout, or None
 
-    def startModule(self, started_callback):
-        super().startModule(started_callback)
+    def startModule(self, start_events):
+        super().startModule(start_events)
         # query unit from tango and update value property
         attrInfo = self._dev.attribute_query('value')
         # prefer configured unit if nothing is set on the Tango device, else