Update ruby

PR to update ruby to 2.1.3, I also made another commit to fix styling using rubocop

Ruby 2.1.3 Changelog
```
This release contains a change of full GC timing to reduce memory consumption (see Bug #9607), and many bugfixes.
```

Ruby 2.1.2 Changelog
```
This release contains a fix for a regression of Hash#reject in Ruby 2.1.1, support for build with Readline-6.3 (see Bug #9578), an updated bundled version of libyaml with psych, and some bug fixes.
```