Travis: Removed jruby-head and added rbx
Travis: Removed jruby-head and added rbx

manastech/ruby-openid,heroku/ruby-openid,fac/ruby-openid,manastech/ruby-openid,heroku/ruby-openid,jonathanleone/ruby-openid,manastech/ruby-openid,jonathanleone/ruby-openid,jonathanleone/ruby-openid,manastech/ruby-openid,manastech/ruby-openid,fac/ruby-openid,heroku/ruby-openid,fac/ruby-openid,jonathanleone/ruby-openid