Add ruby 2.1.0 to Gemfile
Add  rails_12factor gem
Add 'config.serve_static_assets = true'

https://devcenter.heroku.com/articles/ruby-support#injected-plugins
Move font files to public/assets
Fix font path
Revert "Add 'config.serve_static_assets = true'"

This reverts commit dd06c36ace8d3acf3a02fc4eaf0be0769e2b6efb.