Small Stepper Motor - ROB-10551

This pull request is for 3D models of SparkFun's [Small Stepper Motor](https://www.sparkfun.com/products/10551). I've added a 1000x scale STL model, a 1x scale SolidWorks 2010 model, and 1x scale IGES and STEP models.

Dimensions were taken from the datasheet where labeled, with calipers where not labeled, and eyeballed for the fillets. I didn't model in the wires, because I didn't think they'd be that helpful in a 3D model, but I did model the inset area where the wires come out.

Started working on a project using this thing and remembered seeing a post about this repository, so enjoy! Hope it helps.