Remove WIP statement from README

This WIP statement was added 2 years ago. It seems like this project has reached a point of maturity I think it makes sense to remove this.

Author: amilajack

readme.md

@@ -4,8 +4,6 @@ Functional programming (FP) provides many advantages, and its popularity has bee
 
 Examples are presented in JavaScript (ES2015). [Why JavaScript?](https://github.com/hemanth/functional-programming-jargon/wiki/Why-JavaScript%3F)
 
-*This is a [WIP](https://github.com/hemanth/functional-programming-jargon/issues/20); please feel free to send a PR ;)*
-
 Where applicable, this document uses terms defined in the [Fantasy Land spec](https://github.com/fantasyland/fantasy-land)
 
 __Translations__