Updated readme

Author: jbtronics

README.md

@@ -4,6 +4,8 @@
 [![Total Downloads](https://img.shields.io/packagist/dt/florianv/exchanger.svg?style=flat-square)](https://packagist.org/packages/florianv/exchanger)
 [![Version](http://img.shields.io/packagist/v/florianv/exchanger.svg?style=flat-square)](https://packagist.org/packages/florianv/exchanger)
 
+**This is a fork of [florianv/exchanger](https://github.com/florianv/exchanger) for the use in Part-DB.**
+
 Exchanger is a PHP framework to work with currency exchange rates from various services such as
 **[Fixer](https://fixer.io)**, **[Currency Data](https://currencylayer.com)**
 or **[Exchange Rates Data](https://exchangeratesapi.io)**.