Added doc for Nest weather sensors

source/_components/sensor.nest_weather.markdown

@@ -0,0 +1,39 @@
+---
+layout: page
+title: "Nest Weather Sensor"
+description: "Instructions how to integrate Nest sensors within Home Assistant."
+date: 2016-01-13 19:59
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: nest_thermostat.png
+ha_category: Weather
+---
+
+
+The `nest` weather sensor platform let you monitor current weather conditions based on the location of your [Nest](https://nest.com) thermostat.
+
+To set it up, add the following information to your `configuration.yaml` file:
+
+```yaml
+sensor:
+  platform: nest
+  monitored_conditions:
+    - 'weather_temperature'
+    - 'weather_humidity'
+    - 'weather_condition'
+    - 'wind_speed'
+    - 'wind_direction'
+```
+
+Configuration variables:
+
+- **monitored_conditions** array (*Required*): States to monitor.
+    - 'weather_temperature'
+    - 'weather_humidity'
+    - 'weather_condition'
+    - 'wind_speed'
+    - 'wind_direction'
+
+<p class='note'>You must have the [Nest component](/components/nest/) configured to use this sensor.</p>