Banish .DS_Store files!

Here's an easy no-code pull request for ya. I like your fork, and it looks like you've done a lot of good for SVG-edit in general. I may end up using Method Draw in my node-webkit [RoboPaint](https://github.com/techninja/robopaint/) project to replace SVG-edit, which has been shown to be overcomplicated and buggy in many ways.

Here's hoping as I work through it, we'll not only go with it, but I can find more upstream changes to make as I move through. Custom cursors may be one of them.