Added Nest Developer Outbound Port Info (home-assistant#3701)

B1ue-W01f · fabaff · commit 433e95a65297 · 2017-10-22T17:31:11.000+02:00
Configuration fails if outbound port is unavailable. Added info about required port from Known Issues section in: https://github.com/openhab/openhab1-addons/wiki/Nest-Binding
diff --git a/source/_components/nest.markdown b/source/_components/nest.markdown
@@ -34,6 +34,8 @@ The Nest component is the main component to integrate all [Nest](https://nest.co
 9. Once the new product page opens the "Product ID" and "Product Secret" are located on the right side. These will be used as `client_id` and `client_secret` below.
 10. Once Home Assistant is started, a configurator will pop up asking you to log into your Nest account and copy a PIN code into Home Assistant.
 
+Connecting to the Nest Developer API requires outbound port 8553 on your firewall. The configuration will fail if this is not accessible.
+
 ### {% linkable_title Configuration %}
 
 ```yaml
