Add apex to readme list

README.md

@@ -4,6 +4,7 @@ Colorization and configuration supports for multiple languages for the Monaco Ed
 
 ![monaco-languages](https://cloud.githubusercontent.com/assets/5047891/15938606/1fd4bac6-2e74-11e6-8839-d455da8bc8a7.gif)
 
+* apex
 * azcli
 * bat
 * clojure