README.md in protocol-hpack-1.2.0 vs README.md in protocol-hpack-1.2.1

- old
+ new

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 # Protocol::HPACK
 
 Provides a compressor and decompressor for HTTP 2.0 headers, HPACK, as defined by [RFC7541](https://tools.ietf.org/html/rfc7541).
 
 [![Build Status](https://secure.travis-ci.com/socketry/protocol-hpack.svg)](http://travis-ci.com/socketry/protocol-hpack)
+[![Coverage Status](https://coveralls.io/repos/github/socketry/protocol-hpack/badge.svg?branch=master)](https://coveralls.io/github/socketry/protocol-hpack?branch=master)
 
 ## Installation
 
 Add this line to your application's Gemfile: