Update README.md

Author: altenhof

README.md

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 # Java Logging Support for Cloud Foundry
 
+[![Build Status](https://travis-ci.org/SAP/cf-java-logging-support.svg?branch=master)](https://travis-ci.org/SAP/cf-java-logging-support)
 ## Summary
 
 This is a collection of support libraries for Java applications running on Cloud Foundry that serve two main purposes: It provides (a) means to emit *structured application log messages* and (b) instrument parts of your application stack to *collect request metrics*.