new poll mechanism

- remove secop.poller and basic poller
- regular polls for 'important' parameters done by method doPoll
- all other parameters are polled slower (slowInterval) and
  with lower priority (only one at a time when main poll is due)
- nopoll decorator for read_* to disable poll
- enablePoll attribute (default True) for disabling polling a module
- fast polls may be implemented by means of a statemachine
- configurable slow poll interval
+ allow a Parameter to override a Property (parameter
  Readable.pollinterval overrides Module.pollinterval)

Change-Id: Ib1b3453041a233678b7c4b4add22ac399670e447
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/27832
Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>

secop/properties.py

@@ -138,17 +138,18 @@ class HasProperties(HasDescriptors):
         # treat overriding properties with bare values
         for pn, po in properties.items():
             value = getattr(cls, pn, po)
-            if not isinstance(value, Property):  # attribute is a bare value
+            if not isinstance(value, (Property, HasProperties)):  # attribute may be a bare value
+                # HasProperties is a base class of Parameter -> allow a Parameter to override a Property ()
                 po = po.copy()
                 try:
+                    # try to apply bare value to Property
                     po.value = po.datatype(value)
                 except BadValueError:
-                    if pn in properties:
-                        if callable(value):
-                            raise ProgrammingError('method %s.%s collides with property of %s' %
-                                                   (cls.__name__, pn, base.__name__)) from None
-                        raise ProgrammingError('can not set property %s.%s to %r' %
-                                               (cls.__name__, pn, value)) from None
+                    if callable(value):
+                        raise ProgrammingError('method %s.%s collides with property of %s' %
+                                               (cls.__name__, pn, base.__name__)) from None
+                    raise ProgrammingError('can not set property %s.%s to %r' %
+                                           (cls.__name__, pn, value)) from None
                 cls.propertyDict[pn] = po
 
     def checkProperties(self):