title: Install non-editable tag/branch from Git repo with pip
body: <p>I would like to install a non-editable (e.g. no <code>-e</code> option) tag or branch from a Git repo using <a href="http://pip.openplans.org/" rel="noreferrer">pip</a> and cannot seem to find out how to do it.</p>
  
  <p>If I do this:</p>
  
  <pre><code>pip install git+git://github.com/django/django.git@1.2.5#egg=django
  </code></pre>
  
  <p>It just installs Django <code>master</code> branch and not the <code>1.2.5</code> tag. I know that I can install it using the <code>-e</code> option but I don't want to fill up my <code>src</code> dir with packages I am not modifying. This seems like it should be straightforward thing to do but I can't seem how to do it...</p>
  
  <p>Is this possible? If so, how can I accomplish it?</p>
  
  <p>Thanks for any answers!</p>