Use cron job identifier to be able to update command

Change-Id: Id571945585863a08bd2317b57ecc6123a16e1857
diff --git a/README.rst b/README.rst
index 7d67889..51e6370 100644
--- a/README.rst
+++ b/README.rst
@@ -234,6 +234,9 @@
           automatic_reboot_time: "02:00"
 
 Linux with cron jobs
+By default it will use name as an identifier, unless identifier key is
+explicitly set or False (then it will use Salt's default behavior which is
+identifier same as command resulting in not being able to change it)
 
 .. code-block:: yaml
 
@@ -243,6 +246,7 @@
         job:
           cmd1:
             command: '/cmd/to/run'
+            identifier: cmd1
             enabled: true
             user: 'root'
             hour: 2