Flux switch (#523)

* flux switch docs

* fix indentation

source/_components/switch.flux.markdown

@@ -0,0 +1,47 @@
+---
+layout: page
+title: "Flux Switch"
+description: "Instructions how to have switches call command line commands."
+date: 2016-06-01 17:41
+sidebar: true
+comments: false
+sharing: true
+footer: true
+ha_category: Switch
+ha_release: 0.21
+---
+
+The Flux switch platform will change the temperature of your lights similar to
+the way flux works on your computer, using circadian rhythm.  They will be bright
+during the day, and gradually fade to a red/orange at night.
+
+The component will update your lights based on the the time of day.  It will only
+affect lights that are turned on and listed in the flux configuration.
+
+During the day (in between `start time` and `sunset time`), it will fade the lights from
+the `start_colortemp` to the `sunset_colortemp`.  After sunset (between `sunset_time`
+and `stop_time`), the lights will fade from the the `sunset_colortemp` to the
+`stop_colortemp`.  If the lights are still on after the `stop_time` it will continue
+to change the light to the `stop_colortemp` until the light is turned off.  The fade
+effect is created by updating the lights every 30 seconds with a 30 second transition time.
+
+If you don't wish to have flux update on 30 second intervals, you can leave the
+switch turned off and use automation rules that call the service `switch.flux_update`
+whenever you want the lights updated.
+
+Example `configuration.yaml`:
+```yaml
+switch:
+  platform: flux
+  lights:
+    - light.desk
+    - light.lamp
+  name: Fluxer		      # optional, default Flux
+  start_time: 7:00        # optional, default sunrise
+  stop_time: 23:00        # optional, default 22:00
+  start_colortemp: 4000   # optional, default 4000
+  sunset_colortemp: 3000  # optional, default 3000
+  stop_colortemp: 1900    # optional, default 1900
+  brightness: 200         # optional, default calculated by RGB_to_xy
+```
+