Update README.md [ci skip]

Author: olekscode

README.md

@@ -1,5 +1,5 @@
 # DataFrame for Pharo
-[![Project Status: WIP – Initial development is in progress, but there has not yet been a stable, usable release suitable for the public.](http://www.repostatus.org/badges/latest/wip.svg)](http://www.repostatus.org/#wip)
+[![Project Status: Active – The project has reached a stable, usable state and is being actively developed.](http://www.repostatus.org/badges/latest/active.svg)](http://www.repostatus.org/#active)
 [![Build Status](https://travis-ci.org/PolyMathOrg/DataFrame.svg?branch=master)](https://travis-ci.org/PolyMathOrg/DataFrame)
 [![Build status](https://ci.appveyor.com/api/projects/status/1wdnjvmlxfbml8qo?svg=true)](https://ci.appveyor.com/project/olekscode/dataframe)
 [![License](https://img.shields.io/badge/license-MIT-blue.svg)](https://raw.githubusercontent.com/PolyMathOrg/DataFrame/master/LICENSE)