Please create Gemfile and proceed. Gemfile will tells what version of rails should be used.
You can use this Gemfile. https://gist.github.com/sivakumarbdu/0bd29b5ab5113d76e7dc92e9b934c360
Robert O'Connor Yes, we can enable https. I am using webrick server in the example. By editing bin/rails you can enable https, please check http://stackoverflow.com/questions/3640993/how-do-you-configure-webrick-to-use-ssl-in-rails.
Note that, you need have key and crt files. You can get free SSL certificates using https://letsencrypt.org/