.travis.yml in elasticonf-1.1.3 vs .travis.yml in elasticonf-1.1.4

@@ -1,22 +1,26 @@
 language: ruby
 
 rvm:
-  - ruby-head
-  - jruby-head
-  - rbx-head
-  - 2.1.2
-  - 2.1.1
-  - 2.1.0
-  - 2.0.0
-  - 1.9.3
   - 1.9.2
+  - 1.9.3
+  - 2.0.0
+  - 2.1.10
+  - 2.2.9
+  - 2.3.6
+  - 2.4.3
+  - 2.5.0
 
 matrix:
   allow_failures:
-    - rvm: ruby-head
-    - rvm: jruby-head
-    - rvm: rbx-head
+    - rvm: 1.9.2
+    - rvm: 1.9.3
+    - rvm: 2.0.0
+    - rvm: 2.1.10
+    - rvm: 2.2.9
 
 branches:
   only:
-    - master
\ No newline at end of file
+    - master
+
+before_install:
+  - gem install bundler