Update README.md

Author: erikw

README.md

@@ -13,6 +13,10 @@
 [![License](https://img.shields.io/github/license/erikw/nestedtext-ruby?color=informational)](LICENSE.txt)
 [![OSS Lifecycle](https://img.shields.io/osslifecycle/erikw/nestedtext-ruby)](https://github.com/Netflix/osstracker)
 
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+</p>
 
 A ruby library for the human friendly data format [NestedText](https://nestedtext.org/).