fixed this:
[91mTo connect to ftp.ruby-lang.org insecurely, use `--no-check-certificate'.
[0m
[91m!!! Download of https://ftp.ruby-lang.org/pub/ruby/2.1/ruby-2.1.2.tar.bz2 failed!
[0m
The command [/bin/sh -c ruby-install -M https://ftp.ruby-lang.org/pub/ruby ruby 2.1.2] returned a non-zero code: 255