Ruby 2.1.3

This change updates the Travis configuration to test against 2.1.3.

Author: nebhale

.travis.yml

@@ -1,7 +1,7 @@
 ---
 language: ruby
 rvm:
-  - 2.1.2
+  - 2.1.3
   - 1.9.3-p547
 before_script: "if [[ $TRAVIS_RUBY_VERSION != '1.9.3-p547' || $TRAVIS_SECURE_ENV_VARS != 'true' ]]; then unset CODECLIMATE_REPO_TOKEN; fi"
 install: bundle install --deployment --without debug