Execute a command on the command-line.
    :param str,list command: The command to run
    :param bool shell: Whether or not to use the shell.  This is optional; if
        ``command`` is a basestring, shell will be set to True, otherwise it will
        be false.  You can override this behavior by setting this parameter
        directly.
    :param str working_dir: The directory in which to run the command.
    :param bool echo: Whether or not to print the output from the command to
        stdout.
    :param int echo_indent: Any number of spaces to indent the echo for clarity
    :returns: tuple: (return code, stdout)
    Example
        >>> from executor import execute
        >>> return_code, text = execute("dir")

def execute(command, shell=None, working_dir=".", echo=False, echo_indent=0):
    """Execute a command on the command-line.
    :param str,list command: The command to run
    :param bool shell: Whether or not to use the shell.  This is optional; if
        ``command`` is a basestring, shell will be set to True, otherwise it will
        be false.  You can override this behavior by setting this parameter
        directly.
    :param str working_dir: The directory in which to run the command.
    :param bool echo: Whether or not to print the output from the command to
        stdout.
    :param int echo_indent: Any number of spaces to indent the echo for clarity
    :returns: tuple: (return code, stdout)
    Example
        >>> from executor import execute
        >>> return_code, text = execute("dir")
    """
    if shell is None:
        shell = True if isinstance(command, str) else False

    p = Popen(command, stdin=PIPE, stdout=PIPE,
              stderr=STDOUT, shell=shell, cwd=working_dir)

    if echo:
        stdout = ""
        while p.poll() is None:
            # This blocks until it receives a newline.
            line = p.stdout.readline()
            print(" " * echo_indent, line, end="")
            stdout += line

        # Read any last bits
        line = p.stdout.read()
        print(" " * echo_indent, line, end="")
        print()
        stdout += line
    else:
        stdout, _ = p.communicate()

    return (p.returncode, stdout)