.travis.yml in b-1.0.2 vs .travis.yml in b-1.0.3

@@ -1,9 +1,4 @@
 language: ruby
 rvm:
-  - "1.8.7"
-  - "1.9.2"
-  - "1.9.3"
-  - jruby-18mode # JRuby in 1.8 mode
-  - jruby-19mode # JRuby in 1.9 mode
-  - rbx-18mode
-  - rbx-19mode
+  - "2.4.0"
+