[cairo] Hit test path area recipe

[Donn]

> cairo provides cairo_in_stroke() and cairo_in_fill() for doing hit
> testing.
I had a quick look, pity I didn't find them earlier. I was looking in the path 
section of the API... Seemed logical to me :)

Those funcs don't seem to be able to work on a stored path for testing later, 
so ,my routine is still handy. It would be nice if one could:

someotherpath = cr.copy_path_flat()
.
<draw other stuff>
.
result = cr.cairo_in_fill(someotherpath)


\d