introduced attached modules

for the module names, use Attach instead of Property,
which get attached modules automatically before calling initModule

Change-Id: Iff1b37828d4345c03a18ed29b9970bea149a812d
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/21885
Tested-by: JenkinsCodeReview <bjoern_pedersen@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>

secop/modules.py

@@ -407,3 +407,14 @@ class Communicator(Module):
                             result=StringType()
                            ),
     }
+
+
+
+class Attached(Property):
+    # we can not put this to properties.py, as it needs datatypes
+    def __init__(self, attrname=None):
+        self.attrname = attrname
+        super().__init__('attached module', StringType())
+
+    def __repr__(self):
+        return 'Attached(%r)' % self.description