implement __lt__ to support sorting a list of objects

Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>

lib/cdist/core/object.py

@@ -115,6 +115,10 @@ class Object(object):
         """define equality as 'attributes are the same'"""
         return self.__dict__ == other.__dict__
 
+    def __lt__(self, other):
+        return isinstance(other, self.__class__) and self.name < other.name
+
+
     # FIXME: still needed?
     @property
     def explorer_path(self):