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README.md

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 Crisp
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-[![Build Status](https://travis-ci.org/rhysd/Crisp.svg)](https://travis-ci.org/rhysd/Crisp)
+[![Build Status](https://travis-ci.org/rhysd/Crisp.svg?branch=master)](https://travis-ci.org/rhysd/Crisp)
 
 Crisp is one of Lisp dialect which is based on [mal](https://github.com/kanaka/mal) and implemented with [Crystal](https://github.com/manastech/crystal).
 This project is a toy box for my dynamic language ideas.