Add worldclock doc

source/components/sensor.worldclock.markdown

@@ -0,0 +1,34 @@
+---
+layout: page
+title: "Worldclock support"
+description: "Instructions how to integrate a Worldclock within Home Assistant."
+date: 2015-10-02 11:15
+sidebar: false
+comments: false
+sharing: true
+footer: true
+---
+
+<img src='/images/supported_brands/clock.png' class='brand pull-right' />
+The worldclock platform simple displays the current time in a different time zone
+
+To enable this sensor in your installation, add the following to your `configuration.yaml` file:
+
+```yaml
+# Example configuration.yaml entry
+sensor:
+  platform: worldclock
+  time_zone: America/New_York
+  name: New York
+```
+
+Configuration variables:
+
+- **time_zone** (*Required*): The resource or endpoint that contains the value.
+- **name** (*Optional*): The name of the sensor, eg. the city.
+
+For valid time zones check the **TZ** column in the [Wikipedia overview](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones). Or get the full list from the [pytz](https://pypi.python.org/pypi/pytz) module.
+
+```python
+python3 -c "import pytz;print(pytz.all_timezones)"
+```