New port, security/rubygem-openssl: Gem that wraps around OpenSSL library

While there is an OpenSSL gem packaged with Ruby, a separate gem has been
created, so that when OpenSSL security issues arise, the separate gem can
be released independently of Ruby.

WWW: https://github.com/ruby/openssl/

Approved by: swills (mentor)
Differential Revision: https://reviews.freebsd.org/D10415