Sliding achievements fixed

This is just a small bugfix. Any achievements related to sliding, such as Lucky Bulls Eye, Lucky Livin' On The Edge and Luck has nothing to do with it, have apparently been broken for some time. They should now unlock as expected.

So if any of you have been trying to unlock any of these in vain, please forgive me and try again now.

This is only fixed in the windows version for now. Linux and Mac users will have to wait, or contact me and let me know that there are actual players on those platforms who also want this update.