Run make in sphinx' docs directory.

    :return: exit code

def _doc_make(*make_args):
    """Run make in sphinx' docs directory.

    :return: exit code
    """
    if sys.platform == 'win32':
        # Windows
        make_cmd = ['make.bat']
    else:
        # Linux, Mac OS X, and others
        make_cmd = ['make']
    make_cmd.extend(make_args)

    # Account for a stupid Python "bug" on Windows:
    # <http://bugs.python.org/issue15533>
    with cwd(DOCS_DIRECTORY):
        retcode = subprocess.call(make_cmd)
    return retcode