add QubesVM.connected_vms attribute

One more step to core-admin/core-admin-client API compatibility.

qubesadmin/vm/__init__.py

@@ -310,6 +310,18 @@ class QubesVM(qubesadmin.base.PropertyHolder):
             except AttributeError:
                 pass
 
+    @property
+    def connected_vms(self):
+        ''' Return a generator containing all domains connected to the current
+            NetVM.
+        '''
+        for vm in self.app.domains:
+            try:
+                if vm.netvm == self:
+                    yield vm
+            except AttributeError:
+                pass
+
     @property
     def klass(self):
         ''' Qube class '''