more demo test cases

- added them to cfg/dummy_cfg.py
+ treat enum correctly in SecopClient.setParameterFromString

Change-Id: Ia5b2d8d3a21c3215cb93d90975086eb9995b1543

frappy_demo/cryo.py

@@ -161,7 +161,7 @@ class Cryostat(CryoBase):
 
         by setting the current setpoint as new target"""
         # XXX: discussion: take setpoint or current value ???
-        self.write_target(self.setpoint)
+        self.write_target(self.setpoint if self.mode == 'ramp' else self.value)
 
     #
     # calculation helpers

frappy_demo/modules.py

@@ -28,7 +28,7 @@ import time
 from frappy.datatypes import ArrayOf, BoolType, EnumType, \
     FloatRange, IntRange, StringType, StructOf, TupleOf
 from frappy.lib.enum import Enum
-from frappy.modules import Drivable, Readable, Attached
+from frappy.modules import Drivable, Readable, Writable, Attached
 from frappy.modules import Parameter as SECoP_Parameter
 from frappy.properties import Property
 
@@ -99,6 +99,14 @@ class Switch(Drivable):
             self.log.info(info)
 
 
+class BoolWritable(Writable):
+    value = Parameter('boolean', BoolType())
+    target = Parameter('boolean', BoolType())
+
+    def write_target(self, value):
+        self.value = value
+
+
 class MagneticField(Drivable):
     """a liquid magnet
     """