Improved folding.vim file to handle a couple of cases:

• Docstrings get folded even if not directly on the line below a def statement:

def such_a_long_indented_function_could_not_fit_in_one_line(
        arg1=None,
        arg2=None):
    u""" This is my docstring.

    This multiline docstring will be folded.

    """

    s = ''' This simple string
        will not be folded as a docstring. '''

    """ This comment will also be folded

        be folded as a docstring.

    """

• Improved docstring flexibility: u""" and """ and ''' and u''' are recognized as possible docstrings.

• Commented the code for improved readability

• Added a couple of exceptions falsely triggering folding such as @author (a common string in a comment) being recognized as a decorator