Adding ability to set DEFAULT/hostname

Change-Id: I074a7c38d94107818100f499c84ff1633abadf45
diff --git a/README.rst b/README.rst
index dac41c7..561e785 100644
--- a/README.rst
+++ b/README.rst
@@ -565,6 +565,7 @@
       compute:
         version: 2.2
         enabled: True
+        hostname: node-12.domain.tld
         discovery:
           host: 127.0.0.1
         interface: