Updated readme

Author: cmaglie

README.md

@@ -1,11 +1,13 @@
 
-[![GoDoc](https://godoc.org/github.com/arduino/go-properties-map?status.svg)](https://godoc.org/github.com/arduino/go-properties-map)
+[![GoDoc](https://godoc.org/github.com/arduino/go-properties-orderedmap?status.svg)](https://godoc.org/github.com/arduino/go-properties-orderedmap)
 
 Package `properties` is a library for handling maps of hierarchical properties.  
 
 This library is mainly used in the Arduino platform software to handle
 configurations made of key/value pairs stored in files with an INI like
 syntax.
 
+This map also keeps the insertion order when ranging through the `Keys()` method.
+
 For more information read the docs [here](https://godoc.org/github.com/arduino/go-properties-map).