Add Configurate (akullpp#898)

Author: Alexander Söderberg

README.md

@@ -203,6 +203,7 @@ _Libraries that provide external configuration._
 - [centraldogma](https://github.com/line/centraldogma) - Highly-available version-controlled service configuration repository based on Git, ZooKeeper and HTTP/2.
 - [cfg4j](https://github.com/cfg4j/cfg4j) - Modern configuration library for distributed apps written in Java.
 - [config](https://github.com/lightbend/config) - Configuration library supporting Java properties, JSON or its human optimized superset HOCON.
+- [Configurate](https://github.com/SpongePowered/Configurate) - Configuration library with support for various configuration formats and transformations.
 - [dotenv](https://github.com/shyiko/dotenv) - Twelve-factor configuration library which uses environment-specific files.
 - [ini4j](http://ini4j.sourceforge.net) - Provides an API for handling Windows' INI files.
 - [KAConf](https://github.com/mariomac/kaconf) - Annotation-based configuration system for Java and Kotlin.