Add link to wiki about debug F-Droid

README.md

@@ -1,6 +1,7 @@
 [![stable release](https://img.shields.io/badge/release-v0.1.4-blue.svg)](https://github.com/inorichi/tachiyomi/releases)
 [![fdroid release](https://img.shields.io/badge/release-F--Droid-blue.svg)](https://f-droid.org/repository/browse/?fdid=eu.kanade.tachiyomi)
 [![latest debug build](https://img.shields.io/badge/debug-latest%20build-blue.svg)](http://tachiyomi.kanade.eu/latest/app-debug.apk)
+[![fdroid release](https://img.shields.io/badge/debug-F--Droid-blue.svg)](//github.com/inorichi/tachiyomi/wiki/FDroid-for-debug-versions)
 
 ## [Report an issue](https://github.com/inorichi/tachiyomi/blob/master/.github/CONTRIBUTING.md)