memory leak in ImageMetadata.from_buffer

in pyexiv2 0.2.0 for Windows:

in the method

Image::Image(const std::string& buffer, long size)

the buffer gets copied to Exiv2::byte* data , but it is never deleted. You should store the pointer in the Image object, and delete it in ~Image();

The bug becomes obvious with the following little script. It causes out of memory error within 10 seconds:

###########################################################################
import pyexiv2, StringIO
from PIL import Image

def test():
    h = 500
    w = 500
    I = Image.new( "RGB", (w, h) )
    S = StringIO.StringIO( )
    I.save( S, "JPEG", quality = 95)
    jpg_data = S.getvalue()
    while 1:
        metadata = pyexiv2.ImageMetadata.from_buffer(jpg_data)

test()
###########################################################################

Thank you for this very useful module!