drone build badge

README.md

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 Amber
 ====
 
+[![Build Status](https://ci.lolg.it/api/badges/amber/amber/status.svg)](https://ci.lolg.it/amber/amber)
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 Copyright 2011-2015 Nicolas Petton
 
 Copyright 2014-2019 Herbert Vojčík and [Amber contributors](CONTRIBUTORS)