Upgraded ruby version to address ruby security vulnerability CVE-2013-4164

Hey there, noticed there was a ruby patch yesterday addressing a security vulnerability (CVE-2013-4164):

https://www.ruby-lang.org/en/news/2013/11/22/heap-overflow-in-floating-point-parsing-cve-2013-4164/

Ruby 2.0.0 users should set the ruby version to 2.0.0-p353