Add documentation for OASA Telematics greek public transport sensor c (#8978)

* add telematics sensor documentation

* Update source/_components/sensor.oasa_telematics.markdown

Co-Authored-By: panosmz <p.mazarakis94@gmail.com>

* Update source/_components/sensor.oasa_telematics.markdown

Co-Authored-By: panosmz <p.mazarakis94@gmail.com>

* fix route_id type

* rename file & update release no

source/_components/oasa_telematics.markdown

@@ -0,0 +1,72 @@
+---
+layout: page
+title: "OASA Telematics"
+description: "Instructions on how to integrate bus and trolley arrival data for Greek OASA Telematics within Home Assistant."
+date: 2019-03-05 21:52
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: oasa.png
+ha_category:
+  - Transport
+  - Sensor
+ha_iot_class: Cloud Polling
+ha_release: 0.92
+---
+
+The `oasa_telematics` sensor will provide you with bus and trolley arrival times for Greek public transport for Athens, using real-time data from [OASA Telematics](http://telematics.oasa.gr/en/).
+
+## {% linkable_title Configuration %}
+
+Add a sensor to your `configuration.yaml` file as shown in the example:
+
+```yaml
+# Example configuration.yaml entry
+sensor:
+  - platform: oasa_telematics
+    route_id: YOUR_ROUTE_ID
+    stop_id: 'YOUR_STOP_ID'
+```
+
+The `route_id` can be obtained by looking up the "LineCode" of the route you want at this link: 
+
+<http://telematics.oasa.gr/api/?act=webGetLines>
+
+Then getting the "RouteCode" from this link:
+
+<http://telematics.oasa.gr/api/?act=webGetRoutes&p1=LINE_CODE>
+(Replace "LINE_CODE" with the "LineCode" you copied from the first link) find the route you need and copy the `RouteCode` field.
+
+Next, get the `stop_id` from this link: 
+
+<http://telematics.oasa.gr/api/?act=webGetStops&p1=ROUTE_CODE>
+(Replace "ROUTE_CODE" with the "RouteCode" you got from the previous link) find the stop you need and copy the `StopID` field. The route must pass from this stop in order for the sensor to work.
+
+{% configuration %}
+route_id:
+  description: The id of the public transport route.
+  required: true
+  type: int
+stop_id:
+  description: The id of the public transport stop.
+  required: true
+  type: string
+name:
+  description: A friendly name for this sensor.
+  required: false
+  default: OASA Telematics
+  type: string
+{% endconfiguration %}
+
+## {% linkable_title Examples %}
+
+A more extensive example on how to use this sensor:
+
+```yaml
+# Example configuration.yaml entry
+sensor:
+  - platform: oasa_telematics
+    route_id: 1965
+    stop_id: '090006'
+```