Merge "Mention state machine diagram generation in contrib guide"

CONTRIBUTING.rst

@@ -68,6 +68,11 @@ To run the functional tests, use::
 
     tox -e func
 
+Once you have added new state or transition into inspection state machine, you
+should regenerate :ref:`state_machine_diagram` with::
+
+    tox -e genstates
+
 Run the service with::
 
     .tox/py27/bin/ironic-inspector --config-file example.conf

doc/source/workflow.rst

@@ -56,6 +56,8 @@ Usual hardware introspection flow is as follows:
 Starting DHCP server and configuring PXE boot environment is not part of this
 package and should be done separately.
 
+.. _state_machine_diagram:
+
 State machine diagram
 =====================