Test Ruby 2.1.0 via TravisCI

We've already been testing in Ruby 2.1.0 locally, but lets make sure
that contributor's commits are run against 2.1.0 as well.

Change-Id: Ib871fc0166bca2d772983abaf847094ce515d062
Reviewed-on: http://gerrit.causes.com/35915
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>

Author: Shane da Silva

.travis.yml

@@ -3,6 +3,7 @@ rvm:
   - 1.9.2
   - 1.9.3
   - 2.0.0
+  - 2.1.0
 before_script:
   - git config --global user.email "travis@ci.com"
   - git config --global user.name "Travis CI"