message: Added missing property in IEventTelemetry documentation
  * Update API-reference.md
  Added missing property in IEventTelemetry documentation
  * Changed markup of trackEvent field measurements
  Changed markup of trackEvent field measurements to indicate that the field is deprecated
diff: @@ -142,6 +142,7 @@ Parameter | Type | Description
  ---|---|---
  `name` | string | **Required**<br>An event name string.
  `properties?` | dictionary | **Optional**<br>Map of string to any: Additional data used to [filter pages](https://azure.microsoft.com/documentation/articles/app-insights-api-custom-events-metrics/#properties) in the portal. Defaults to empty.
  +~~`measurements?`~~ | dictionary | **Optional**<br>Map of string to any: Additional data (metrics) used to [filter pages](https://azure.microsoft.com/documentation/articles/app-insights-api-custom-events-metrics/#properties) in the portal. Defaults to empty.
  ### flush
  