Add irish rail docs (#3633)

* Add irish rail docs

* make main example be basic

* Small spelling & grammar fixes

source/_components/sensor.irish_rail_transport.markdown

@@ -0,0 +1,52 @@
+---
+layout: page
+title: "Irish Rail Transport"
+description: "Instructions on how to integrate timetable data for traveling on Irish Rail within Home Assistant."
+date: 2017-10-15 16:50
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: irishrail.png
+ha_category: Transport
+ha_iot_class: "Cloud Polling"
+ha_release: 0.56
+---
+
+
+The `irish_rail_transport` sensor will give you the time until the next two departures (within 90 minutes) from an Irish Rail station using the RTPI information.
+
+A station name is the full station name as specified on the Irish Rail search site, for example, `Tara Street` or `Dublin Connolly`.
+
+To activate the sensor add the data to your `configuration.yaml` file as shown in the example:
+
+```yaml
+# Example configuration.yaml entry
+sensor:
+  - platform: irish_rail_transport
+    station: "Tara Street"
+    name: "To Greystones"
+```
+
+Configuration variables:
+
+- **station** (*Required*): The name of the station.
+- **direction** (*Optional*): The direction of the train. Typically either `Northbound` or `Southbound`.
+- **destination** (*Optional*): The name of the destination station to filter by.
+- **stops_at** (*Optional*): An optional filter based on the name of a station that the train stops at.
+- **name** (*Optional*): A friendly name for this sensor.
+
+Using the `stops_at` option will cause an extra request per train found. Therefore, if you are looking at a busy station, it is recommended that you also use at least one other filter. For example:
+
+```yaml
+# Example full configuration.yaml entry
+sensor:
+  - platform: irish_rail_transport
+    station: "Tara Street"
+    direction: Southbound
+    destination: Greystones
+    stops_at: "Dun Laoghaire"
+    name: "To Greystones"
+```
+
+The above example will show the next 2 `Southbound` trains that leave `Tara Street` station, going to `Greystones` via `Dun Laoghaire`: