This because in Ubuntu 14.04 stopply to Ruby 1.9.*

Install Ruby.md

• http://stackoverflow.com/a/1403294/3445802
• https://gorails.com/setup/ubuntu/14.04

$ wget http://ftp.ruby-lang.org/pub/ruby/2.2/ruby-2.2.3.tar.gz
$ tar -xzvf ruby-2.2.3.tar.gz
$ cd ruby-2.2.3/
$ ./configure
$ make
$ sudo make install
$ sudo ln -sf /usr/local/bin/ruby /usr/bin/ruby
$ ruby -v
$ sudo apt-get install nodejs

Github Pages

$ sudo gem install bundler
$ sudo gem install github-pages
$ sudo gem install public_suffix -v '1.5.3' <only if have a problem>
$ bundle install
$ bundle exec jekyll serve