Define archetype in plenary object template

- archetype name assigned to /system/archetype/name

Change-Id: Ice4559238bb36e299fc0f172c2fc13f357c9f13f

Author: jouvin

lib/aquilon/worker/templates/host.py

@@ -233,6 +233,7 @@ def body(self, lines):
 
         lines.append("")
         dbos = self.dbobj.operating_system
+        pan_assign(lines, "system/archetype/name", self.dbobj.archetype.name)
         pan_assign(lines, "system/archetype/os", dbos.name)
         pan_assign(lines, "system/archetype/model", dbos.version)
         pan_assign(lines, "system/archetype/os_lifecycle", dbos.lifecycle)