Remove defunct ci badge

Author: turt2live

README.md

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 # node-email-reply-parser
 
 [![npm version](https://badge.fury.io/js/node-email-reply-parser.svg)](https://www.npmjs.com/package/node-email-reply-parser)
-[![TravisCI badge](https://travis-ci.org/turt2live/node-email-reply-parser.svg?branch=master)](https://travis-ci.org/turt2live/node-email-reply-parser)
 
 A port of willdurand/EmailReplyParser (which is a port of github/email_reply_parser) to nodejs