title: Pip install without progress bars
body: <p>In my Django application I have a circle.yml file that runs 'pip install -r requirements/base.txt'. When I push up code, and check the CircleCI logs when there is an error, its hard to get to because there are so many dependencies and as of pip6 they started showing progress bars for the installations. Because of that it get busy pretty quick. I read on pip's github page that a few people were requesting a flag to the install command to remove the progress bars, but continue to show everything else like exceptions. something like </p>
  
  <p><code>pip install --no-progress-bar foo</code> </p>
  
  <p><a href="https://github.com/pypa/pip/pull/4194" rel="noreferrer">https://github.com/pypa/pip/pull/4194</a>. It doesn't look like this has been released yet though. Is there any way to currently do this without using --<strong>no-cache-dir</strong> ?</p>