README: Remove old invalid link

Signed-off-by: Daijiro Fukuda <[email protected]>

Author: daipom

README.md

@@ -1,7 +1,5 @@
 # fluent-plugin-remote_syslog
 
-[![Build Status](https://travis-ci.org/dlackty/fluent-plugin-remote_syslog.svg?branch=master)](https://travis-ci.org/dlackty/fluent-plugin-remote_syslog)
-
 [Fluentd](http://fluentd.org) plugin for output to remote syslog serivce (e.g. [Papertrail](http://papertrailapp.com/))
 
 ## Requirements