Passing variables to scripts (#1140)

Explain how to pass variables along to scripts in more detail, using actual examples instead of JSON code. Not alot of people are aware of this (previously) nearly undocumented feature.

source/_components/script.markdown

@@ -52,20 +52,57 @@ script:
           entity_id: group.living_room
 ```
 
-### {% linkable_title Passing parameters in service calls %}
+### {% linkable_title Passing variables to scripts %}
 
-As part of the service, parameters can be passed in that will be made available to the script as variables within templates.
+As part of the service, variables can be passed along to a script so they become available within templates in that script.
 
-There are two ways to activate scripts. One is using the generic `script.turn_on` service. To pass variables to the script with this service, call it using the following parameters:
+There are two ways to achieve this. One way is using the generic `script.turn_on` service. To pass variables to the script with this service, call it with the desired variables:
 
 ```yaml
-{
+# Example configuration.yaml entry
-  "entity_id": "script.wakeup",
+automation:
-  "variables": {
+  trigger:
-    "hello": "world",
+    platform: state
-    "name": "Paulus"
+    entity_id: light.bedroom
-  }
+    from: 'off'
-}
+    to: 'on'
+  action:
+    service: script.turn_on
+    entity_id: script.notify_pushover
+    data:
+      variables:
+        title: 'State change'
+        message: 'The light is on!'
 ```
 
-If you are calling the script service directly, for example `script.wakeup`. All service data will be made available as variables.
+The other way is calling the script as a service directly. In this case, all service data will be made available as variables. If we apply this approach on the script above, it would look like this:
+
+```yaml
+# Example configuration.yaml entry
+automation:
+  trigger:
+    platform: state
+    entity_id: light.bedroom
+    from: 'off'
+    to: 'on'
+  action:
+    service: script.notify_pushover
+    data:
+      title: 'State change'
+      message: 'The light is on!'
+```
+
+Using the variables in the script requires the use of `data_template`:
+```yaml
+# Example configuration.yaml entry
+script:
+  notify_pushover:
+    sequence:
+      - condition: state
+        entity_id: switch.pushover_notifications
+        state: 'on'
+      - service: notify.pushover
+        data_template:
+          title: "{{ title }}"
+          message: "{{ message }}"
+```