Merge "Add release note for "network delete" command for nova network"

Author: Jenkins

releasenotes/notes/bug-1543672-bad2fc4c6c8f3125.yaml

@@ -0,0 +1,4 @@
+---
+features:
+  - Command ``network delete`` is now available for nova network.
+    [Bug `1543672 <https://bugs.launchpad.net/python-openstackclient/+bug/1543672>`_]