title: First deploy fails in Capistrano 3 with a /var/www/XXX permission error
body: <p>I am running the first deploy to a machine via <code>cap staging deploy</code>. As of Cap3, <code>deploy:setup</code> is no longer needed. Yet, strangely, I get a mkdir permissions error:</p>
  
  <pre><code> INFO[cb348f12] Running /usr/bin/env mkdir -pv /var/www/myapp/shared /var/www/myapp/releases on ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com
   DEBUG[cb348f12] Command: /usr/bin/env mkdir -pv /var/www/myapp/shared /var/www/myapp/releases
   DEBUG[cb348f12]    mkdir: 
   DEBUG[cb348f12]    cannot create directory ‘/var/www’
   DEBUG[cb348f12]    : Permission denied
   DEBUG[cb348f12]    
   DEBUG[cb348f12]    mkdir: 
   DEBUG[cb348f12]    cannot create directory ‘/var/www’
   DEBUG[cb348f12]    : Permission denied
   DEBUG[cb348f12]    
   cap aborted!
   SSHKit::Runner::ExecuteError: Exception while executing on host ec2-xx-xx-xx-xx.us-west-2.compute.amazonaws.com: mkdir exit status: 1
  </code></pre>
  
  <p>Of course, I could go an create and chmod that directory myself, but that's not the point. Cap3 is supposed to take care of that itself. I'm confused why it doesn't do that. I should also note that I had this same setup succeed before with another machine (though that was "production" environment).</p>
  
  <p>Here are some basic settings in my deploy.rb:</p>
  
  <pre><code> set :application, "myapp"
   set :user, 'ec2-user'
  </code></pre>