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README.md

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-# An ACME Shell script: acme.sh
+# An ACME Shell script: acme.sh [![Build Status](https://travis-ci.org/Neilpang/acme.sh.svg?branch=master)](https://travis-ci.org/Neilpang/acme.sh)
 - An ACME protocol client written purely in Shell (Unix shell) language.
 - Fully ACME protocol implementation.
 - Simple, powerful and very easy to use. You only need 3 minutes to learn.