Update ES2018.MD

Author: daumann

ES2018.MD

@@ -2,7 +2,7 @@
 
 See the [ES2018 standard](http://www.ecma-international.org/ecma-262/9.0/) for full specification of the ECMAScript 2018 language.
 
-ES9 includes the following new feature proposals:
+ES2018 includes the following new feature proposals:
 
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