windows: drop support

I've checked with the kde-windows room and we've conclude that this probably isn't used. let's remove it and see who comes out of the woodwork.

this code hasn't really seen any changes making me question it's quality. at the same time it is very questionable anyway: windows has it's own crash handling infrastructure, drkonqi is only getting in the way there.

this is a first step towards reducing the infrastructure code for multiple debuggers