Dedent section starting with .. deprecation::

[stefanv]

Closes #573

There may be a more elegant way to fix this. Problem is that section that starts with deprecation warning comes back indented, and therefore fails to meet the test doc.extended_summary.startswith(".. deprecated:: ").

Reproducer:

foo.py:

def my_func_right():
    """Compute my function.

    .. deprecated:: v0.1
        This function is listed for future removal.

    What it does in more detail.
    """
    pass

$ numpydoc lint foo.py

[stefanv]

@rossbar @larsmans I think this is ready. It does close an issue, and I think it is an innocuous change. Users should not be forced to add a new section just to indicate that a docstring is deprecated (see original issue #573).

[larsoner]

@stefanv would it be easy to add a regression test for this? If it's a pain I think we can get away without it

[stefanv]

Of course!