Remove leftovers from the Travis builds

Author: tbroyer

README.md

@@ -1,8 +1,6 @@
 gwt-maven-plugin
 ================
 
-[![Build Status](https://travis-ci.org/tbroyer/gwt-maven-plugin.png?branch=master)](https://travis-ci.org/tbroyer/gwt-maven-plugin)
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 This plugin aims at making it easier to build GWT projects with Maven, by providing two specific packagings: `gwt-lib` and `gwt-app`.
 
 Basic usage