Add documentation for workday sensor (#2254)

source/_components/binary_sensor.workday.markdown

@@ -0,0 +1,50 @@
+---
+layout: page
+title: "Workday Binary Sensor"
+description: "Steps to configure the binary workday sensor."
+date: 2017-03-13 21:30
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: home-assistant.png
+ha_category: Binary Sensor
+ha_iot_class: "Local Polling"
+ha_release: 0.40.1
+---
+
+The `workday` binary sensor indicates, whether the current day is a workday or not. It allows specifying, which days of the week counts as workdays and also uses the python module [holidays](https://pypi.python.org/pypi/holidays) to incorporate information about region-specific public holidays.
+
+```yaml
+# Example configuation.yaml entry
+binary_sensor:
+  - platform: workday
+    country: DE
+    province: BW
+```
+
+Configuration variables:
+
+- **country** (*Required*): Country code according to [holidays](https://pypi.python.org/pypi/holidays/0.8.1) notation.
+- **province** (*Optional*): Province code according to [holidays](https://pypi.python.org/pypi/holidays/0.8.1) notation (defaults to None).
+- **workdays** (*Optional*): List of workdays (defaults to mon, tue, wed, thu, fri).
+- **excludes** (*Optional*): List of workday excludes (defaults to sat, sun, holiday).
+
+Days are specified as follows: `mon`, `tue`, `wed`, `thu`, `fri`, `sat`, `sun`. The keyword `holiday` is used for public holidays identified by the holidays module.
+
+
+Example usage for automation:
+```yaml
+automation:
+  alias: Turn on heater on workdays
+  trigger:
+    platform: time
+    after: '08:00:00'
+  condition:
+    condition: state
+    entity_id: 'binary_sensor.workday_sensor'
+    state: 'off'
+  action:
+    service: switch.turn_on
+    entity_id: switch.heater
+```