Fixing indentation in 'create action' tutorial

Partially implements blueprint mistral-documentation

Change-Id: I50fa230684b4ef64f7f6ae81d342d670eb5bf695

doc/source/developer/creating_custom_action.rst

@@ -1,8 +1,10 @@
+=============================
 How to write an Action Plugin
 =============================
 
 1. Write a class inherited from mistral.actions.base.Action
-::
+
+ .. code-block:: python
 
     from mistral.actions import base
 
@@ -15,34 +17,37 @@ How to write an Action Plugin
             # return your results here
             return {'status': 0}
 
-2. Publish the class in a namespace
-   (in your setup.cfg)
 
-::
+2. Publish the class in a namespace (in your ``setup.cfg``)
+
+
+ .. code-block:: ini
 
    [entry_points]
    mistral.actions =
        example.runner = my.mistral_plugins.somefile:RunnerAction
 
 3. Reinstall Mistral if it was installed in system (not in virtualenv).
-4. Run Db-sync tool via either::
 
-    *tools/sync_db.sh --config-file <path-to-config>*
+4. Run db-sync tool via either
 
-or::
+ .. code-block:: console
 
-    *mistral-db-manage --config-file <path-to-config> populate*
+    $ tools/sync_db.sh --config-file <path-to-config>
 
-5. Use your plugin
+ or
 
- * Now you can call the action "example.runner"
+ .. code-block:: console
 
-::
+    $ mistral-db-manage --config-file <path-to-config> populate
 
- Workflow:
+5. Now you can call the action ``example.runner``
+
+  .. code-block:: yaml
+
+    my_workflow:
       tasks:
-     myaction:
+        my_action_task:
           action: example.runner
-       parameters:
+          input:
             param: avalue_to_pass_in
-