Sturdy top mount spool holder

**Top mount spool holder for Robo 3D R1 and R1+**

Ground up redesign inspired by things [1773428](https://www.thingiverse.com/thing:1773428) and [158289](https://www.thingiverse.com/thing:158289). Wanted something that would hold the wheels a little more ridged and fit the shape of the R1 a little closer.

Can be used with my [spool enclosure design](https://www.thingiverse.com/thing:2849617) to make your printer look like a robot

**2018-01-21 Update**
Needed to print using a very small spool and the old version wouldn't support it. The new version insets the screw heads on one side so the supports can be pressed flush against each other. A filament guide hole was also added to the middle.

**2018-01-25 Update**
It turns out the half filament guide on each side of the support really only works when they are flush, but if even a little apart the filament can get snagged. So I cut out the space needed for the stock filament guide so that can always be used. Doesn't affect st