Currently, neutron core resources (like net, subnet, port and subnetpool)
do not save time-stamps upon their creation and updation. This
information can be critical for debugging purposes.
This patch introduces a new extension called "timestamp" extending existing
the neutron core resources to allow their creation and modification times
to be record. Now this patch add this resource schema and the functions which
listen db events to add timestamp fields.
APIImpact
DocImpact: Neutron core resources now contain 'timestamp' fields like
'created_at' and 'updated_at'
Change-Id: I24114b464403435d9c1e1e123d2bc2f37c8fc6ea
Partially-Implements: blueprint add-port-timestamp
4c2c983618