added Oxford comma

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branch : readme-edit

readme.md

@@ -1,4 +1,4 @@
-LÖVE is an *awesome* framework you can use to make 2D games in Lua. It's free, open-source, and works on Windows, Mac OS X, Linux, Android and iOS.
+LÖVE is an *awesome* framework you can use to make 2D games in Lua. It's free, open-source, and works on Windows, Mac OS X, Linux, Android, and iOS.
 
 [![Build Status: Windows](https://ci.appveyor.com/api/projects/status/u1a69u5o5ej1pus4?svg=true)](https://ci.appveyor.com/project/AlexSzpakowski/love)