title: PIP install error with git repository packages
body: <p>I have a old django project needs to deploy now. I need to install the exact versions used in this project.</p>
  
  <p>In this project's requirements.txt there are some packages which are from GIT repos.</p>
  
  <p>while installing those requirements using </p>
  
  <p><code>pip install -r requirements.txt</code> its throwing following error.</p>
  
  <pre><code>  File "/home/nyros/Desktop/new/rmkenv/local/lib/python2.7/site-packages/pip/req.py", line 70, in __init__
      req = pkg_resources.Requirement.parse(req)
    File "/home/nyros/Desktop/new/rmkenv/local/lib/python2.7/site-packages/pip/_vendor/pkg_resources.py", line 2606, in parse
      reqs = list(parse_requirements(s))
    File "/home/nyros/Desktop/new/rmkenv/local/lib/python2.7/site-packages/pip/_vendor/pkg_resources.py", line 2544, in parse_requirements
      line, p, specs = scan_list(VERSION,LINE_END,line,p,(1,2),"version spec")
    File "/home/nyros/Desktop/new/rmkenv/local/lib/python2.7/site-packages/pip/_vendor/pkg_resources.py", line 2512, in scan_list
      raise ValueError("Expected "+item_name+" in",line,"at",line[p:])
  ValueError: ('Expected version spec in', 'django_filebrowser-origin/HEAD', 'at', '/HEAD')
  
  Storing debug log for failure in /home/nyros/.pip/pip.log
  </code></pre>
  
  <p>I thinks the problem is with git urls in the requirements.txt . Please check the following requirements.txt and let me know what to modify to install requirements.</p>
  
  <pre><code>-e hg+https://bitbucket.org/descent/django-aloha@844a88f99fba4fd3e29771fe85d6c611e66cd2e5#egg=django_aloha-dev
  
  -e git+https://github.com/Bouke/django-filebrowser-no-grappelli.git@a367570e795288281be303f7c2505803f7a48543#egg=django_filebrowser-origin/HEAD
  
  
  
  -e git+https://github.com/toastdriven/django-haystack.git@4d90d7d6c77ebf7ee298f2de941b1f41d99caf1d#egg=django_haystack-master
  
  
  
  -e git+https://github.com/jowolf/django-ide.git@a2aa7a8ae41298c4635ba6c8c3b634a130c653d9#egg=django_ide-master
  
  -e git+https://github.com/bread-and-pepper/django-userena.git@5beff3929f261694f9af03f940e500586e2a60d3#egg=django_userena-origin/HEAD
  
  
  
  -e git+https://github.com/pythonforfacebook/facebook-sdk@a12457671d3cb6265c52d9e8ef1ea2b387299fe3#egg=facebook_sdk-master
  </code></pre>