Add Documentation for Netatmo Welcome (#542)

* Reorganize  documentation for Netatmo

As Netatmo is now a Hub component, documentations has been splitted in several
parts betweent the hub, the sensors and the camera

Signed-off-by: Hugo D. (jabesq) <jabesq@gmail.com>

* Add configuration variables for Netatmo Welcome cameras

* Add ha_release information on new documentation pages

* Netatmo Weather Station is a weather sensor

source/_components/camera.netatmo.markdown

@@ -0,0 +1,37 @@
+---
+layout: page
+title: "Netatmo Camera"
+description: "Instructions how to integrate Netatmo camera into Home Assistant."
+date: 2016-06-02 08:10
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: netatmo.png
+ha_category: Camera
+ha_release: "0.2x"
+---
+
+
+The `netatmo` camera platform is consuming the information provided by a [Netatmo Welcome](https://www.netatmo.com) camera. This component allows you to view the current photo created by the Camera.
+
+To enable the Netatmo camera, add the following lines to your `configuration.yaml`:
+
+```yaml
+# Example configuration.yaml entry
+camera:
+  platform: netatmo
+  home: home_name
+  cameras:
+    - camera_name1
+    - camera_name2
+```
+
+Configuration variables:
+
+- **home** (*Optionnal*): Will display the cameras of this home only.
+- **cameras** array (*Optionnal*): Cameras to use. Multiple enties allowed.
+    - **camera_name**: Name of the camera to display.
+
+If **home** and **cameras** is not provided, all cameras will be displayed.
+