Added Ruby 2.4.1 to Travis configuration (#20)

* [ruby-2.4] added ruby 2.4.1 to travis yml

* [ruby-2.4] updated changelog

Author: portertech

.travis.yml

@@ -8,6 +8,7 @@ rvm:
 - 2.1
 - 2.2
 - 2.3.0
+- 2.4.1
 notifications:
   email:
     recipients:
@@ -30,4 +31,5 @@ deploy:
     rvm: 2.1
     rvm: 2.2
     rvm: 2.3.0
+    rvm: 2.4.1
     repo: sensu-plugins/sensu-plugins-filesystem-checks

CHANGELOG.md

@@ -4,6 +4,8 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 This CHANGELOG follows the format listed at [Keep A Changelog](http://keepachangelog.com/)
 
 ## [Unreleased]
+### Added
+- Added testing on Ruby 2.4.1 (@portertech)
 
 ## [1.0.0] - 2017-07-01
 ### Added