Added jruby as one of the possible Cloudfile ruby_versions. [#47427257]
Thins number is configured by app during cloudfile creation. [#47427337]
When running under jruby ruby_version in newly generated Cloudfile is set to jruby. [#47427257]
When running under jruby puma instead of thin is used as a web server. [#47427337]
Merge pull request #74 from shellycloud/jruby-fixes

JRuby fixes for shelly add