title: heroku console show the latest sha hash from git deployment
body: <p>I have a development branch hosted on Heroku and we have a couple of people using this branch to look for bugs, it would be nice to show the SHA-1 Hash of the commit that's the latest deployed on Heroku so that we know which bugs belong to which commit.</p>
  
  <p>But I cannot at all find any way to find this information. nothing in the ENV variable in heroku run console. Though "heroku releases" does show a list of deployment info, including the first few character of the SHA-1 hash, that leads me to think that Heroku must store it somehwere, but I just cannot find where. Does anyone know?</p>
  
  <p>I realize that I haven't really put down the question as clear as I should: I meant to find the SHA-1 hash inside Rails on Heroku. Like I can do something like this:</p>
  
  <pre><code>&lt;h1&gt;&lt;%= ENV['REV']&lt;/h1&gt;
  </code></pre>
  
  <p>Thank You!</p>