New effect extension: Image frames

[Roggan]

I've written a Python script that's adding simple frames with drop shadows to all selected images. Nothing fancy, but somtimes handy.

The attachment includes the required files and a small demo image of how the extension could be used.

For some reason, the gaussian blur requires a lot of cpu, and I think it might be due to the filter's width, height, x and y values. I haven't found out any good way to calculate the proper values, so I've just inserted some values big enough. If you have any points here, please let me know :) Any feedback is of course welcome!