Change Travis JRuby to default and allow failures.

Author: gkellogg

.travis.yml

@@ -6,10 +6,11 @@ env:
 rvm:
   - 2.2.5
   - 2.3.1
-  - jruby-9.1.2.0
+  - jruby
   - rbx
 cache: bundler
 sudo: false
 matrix:
   allow_failures:
-      - rvm: rbx
+    - rvm: rbx
+    - rvm: jruby