title: bundle vs bundler / bundle vs bundle install
body: <ol>
  <li><p>What is the difference between the <code>bundle</code> &amp; <code>bundler</code> commands?</p></li>
  <li><p>What is the difference between <code>bundle</code> &amp; <code>bundle install</code>?</p></li>
  <li><p>If there're no differences, why have multiple commands that do the same thing?</p></li>
  </ol>