ruby: update to 2.1.4

This release includes security fixes for the following vulnerabilities:

* CVE-2014-8080: Denial of Service XML Expansion
* Changed default settings of ext/openssl related to CVE-2014-3566

And there are some bug-fixes.

Ref: https://www.ruby-lang.org/en/news/2014/10/27/ruby-2-1-4-released/

Signed-off-by: Luiz Angelo Daros de Luca <luizluca@gmail.com>
Merge pull request #527 from luizluca/ruby-update

ruby: update to 2.1.4