Simple springy clip for wide things

I wanted to clip a cutting mat to my print bed as part of [using my 3D printer as a plotter](http://www.thingiverse.com/thing:1987629). The print bed is thick, so I needed a clip that could span it. Hence, this ugly but functional solution. You can customize it all sorts of ways, but I printed it with the bottom jaw toothy and top jaw smooth, and glued a bit of rubber from an old bicycle inner tube with Shoe Goo to the top jaw.

The default dimensions are for the DaVinci 1.0a.

**March 6, 2019:** Revised with smaller angle and rounded handle, using (and bundling) [my Bezier library](https://www.thingiverse.com/thing:2207518).