title: Folder for data_files in setup.py build (setuptools)
body: <p>I am trying to add <code>data_file</code> to <code>setup.py</code> project . I can use file from <code>/tmp/</code> directory, and cannot use it from current directory of the script:</p>
  
  <pre><code>from setuptools import setup, find_packages
  import os
  
  packages = find_packages("src")
  foo_path = os.path.dirname(os.path.abspath(__file__)) + '/foo.dat'
  print foo_path   # file exists and there full absolute path is printed:
                   # '/home/loom/myapp/foo.dat'
  
  setup(name='myapp',
          version='0.2.0',
          url='http://loom.st',
          author='Loom',
          author_email='admin@loom.st',
          package_dir={'': 'src'},
          packages=packages,
          py_modules=['my_start'],
  # 1.        data_files=[('lib/python', [foo_path])],
  # 2.        data_files=[('lib/python', [/tmp/foo.dat])],
          setup_cfg=True,
          )
  </code></pre>
  
  <p>When the line <code>1.</code> is uncommented, then <code>python setup.py bdist_rpm</code> failed with message:</p>
  
  <pre><code>running install_data
  error: can't copy '/home/loom/myapp/build/bdist.linux-x86_64/rpm/BUILD/myapp-0.2.0/foo.dat': doesn't exist or not a regular file
  error: Bad exit status from /var/tmp/rpm-tmp.02mmV8 (%install)
  </code></pre>
  
  <p>When the line <code>2.</code> is uncommented, then build is completed ok and includes <code>foo.dat</code> (file <code>/tmp/foo.dat</code> exists)</p>
  
  <p>Why the line <code>1.</code> induces error and how to avoid it?</p>