Merge pull request #519 from codacy-badger/codacy-badge-1

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README.md

 DMDirc plugins
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+[![Codacy Badge](https://api.codacy.com/project/badge/Grade/920da51fe86c4341a2ffa320d531cad3)](https://www.codacy.com/app/DMDirc/Plugins?utm_source=github.com&utm_medium=referral&utm_content=DMDirc/Plugins&utm_campaign=badger)
+
 This repository contains plugins for [DMDirc](https://www.dmdirc.com/), a Java
 IRC client.