manager: don't schedule to non-schedule_enabled Node

circle/manager/scheduler.py

@@ -56,7 +56,7 @@ def select_node(instance, nodes):
     '''
     # check required traits
     nodes = [n for n in nodes
-             if n.enabled and n.online
+             if n.schedule_enabled and n.online
              and has_traits(instance.req_traits.all(), n)]
     if not nodes:
         logger.warning('select_node: no usable node for %s', unicode(instance))