title: Heroku csv gem not found
body: <p>I put in my gemfile
  gem 'csv'
  because I use csv in my code.</p>
  
  <p>When I run locally everything is fine.</p>
  
  <p>However, when I push it to heroku (which worked previously), the whole thing crashes and I get an error that a csv gem could not be found.</p>
  
  <p>However, when I remove it, everything works including the code involving the CSV.</p>
  
  <p>Is it fine to just omit it?</p>