update build icon

Author: BrandonArp

README.md

@@ -5,9 +5,9 @@ Metrics Client Apache HTTP Sink
     <img src="https://img.shields.io/hexpm/l/plug.svg"
          alt="License: Apache 2">
 </a>
-<a href="https://travis-ci.org/ArpNetworking/metrics-apache-http-sink-extra/">
-    <img src="https://travis-ci.org/ArpNetworking/metrics-apache-http-sink-extra.png?branch=master"
-         alt="Travis Build">
+<a href='https://build.arpnetworking.com/job/ArpNetworking/job/metrics-apache-http-sink-extra/job/master/'>
+    <img src='https://build.arpnetworking.com/job/ArpNetworking/job/metrics-apache-http-sink-extra/job/master/badge/icon'
+         alt="Jenkins Build">
 </a>
 <a href="http://search.maven.org/#search%7Cga%7C1%7Cg%3A%22com.arpnetworking.metrics.extras%22%20a%3A%22apache-http-sink-extra%22">
     <img src="https://img.shields.io/maven-central/v/com.arpnetworking.metrics.extras/apache-http-sink-extra.svg"