Create empty action groups

This introduces the framework for set speed events to have the groups
within an event assign directly on the event action. When a group is
defined directly to an action, it will be used in place of the group(s)
on the event. This allows a single event, driven by trigger(s), to call
multiple actions on different groups with differing parameters to those
actions.

Change-Id: I5c648d912641b3006a77eab27457e3ddb220c2ad
Signed-off-by: Matthew Barth <msbarth@us.ibm.com>
diff --git a/control/templates/defs.mako b/control/templates/defs.mako
index 5356677..3a68e99 100644
--- a/control/templates/defs.mako
+++ b/control/templates/defs.mako
@@ -60,6 +60,7 @@
 %endfor
 %endfor
 },
+{Group{},
 std::vector<Action>{
 %for a in event['action']:
 %if len(a['parameters']) != 0:
@@ -76,7 +77,7 @@
 %endfor
 ),
 %endfor
-},
+}},
 std::vector<Trigger>{
     %if ('timer' in event['triggers']) and \
         (event['triggers']['timer'] is not None):