Schedule API documentation.

docs/engine-features.md

@@ -84,4 +84,8 @@ The Swagger Specification of a Track Service entry as YAML looks like this:
 
 **Reporting API**: Create monthly reports using this endpoint.
 
-* `api/v1/report/$MONTH` ...... Returns all playout details for the given month in the format `YYYY-MM`
\ No newline at end of file
+* `/api/v1/report/$MONTH` ...... Returns all playout details for the given month in the format `YYYY-MM`
+
+**Schedule API**: Retrieves information on the programme.
+
+* `/api/v1/schedule/upcoming` .. Returns the next three schedules, after the one currently playing.