Update sensor.usps.markdown (home-assistant#1803)

officiallybob · fabaff · commit e1cf7a99ab43 · 2017-01-17T20:54:07.000+01:00
* Update sensor.usps.markdown

Added more information on Opting In to MY USPS.

* Update sensor.usps.markdown
diff --git a/source/_components/sensor.usps.markdown b/source/_components/sensor.usps.markdown
@@ -13,6 +13,7 @@ ha_release: 0.36
 ---
 
 The `usps` platform allows one to track deliveries by the [US Postal Service (USPS)](https://www.usps.com/).
+In addition to having a USPS account, you will need to complete the "Opt-In" process by clicking "Get Started Now" on [this page](https://my.usps.com/mobileWeb/pages/intro/start.action). Currently, you also will need to have a package listed in the "Package Dashboard" in order for the component to complete set-up.
 
 To enable this sensor, add the following lines to your `configuration.yaml`:
 
