Added tapsaff documentation (#2746)

* Added tapsaff documentation

* Add description for the configuration variables

source/_components/binary_sensor.tapsaff.markdown

@@ -0,0 +1,32 @@
+---
+layout: page
+title: "Taps Aff"
+description: "Instructions how to use the Taps Aff binary sensor in Home Assistant."
+date: 2017-05-28 18:00
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: tapsaff.png
+ha_category: Weather
+featured: false
+ha_release: 0.47
+ha_iot_class: "Local Polling"
+---
+
+
+The `tapsaff` binary sensor provides the 'Taps Aff' status for a given location within the UK using [Taps Aff](http://www.taps-aff.co.uk). 
+
+To enable this sensor, add the following lines to your `configuration.yaml`:
+
+```yaml
+# Example configuration.yaml entry
+binary_sensor:
+  - platform: tapsaff
+    location: glasgow
+```
+
+Configuration variables:
+
+- **location** (*Required*): The location for the Taps Aff. It must be configured with a UK postcode or city to work. 
+- **name** (*Optional*): The name to use when displaying this sensor.