Cable chain with limiter (surfaces fixed)

This is a model cleanup of ld3300's Cable chain with limiter, which was itself a modification to johnniewhiskey's original Ender 3 cable chain. ld3300's variant adds a travel limiter to the original cable chain which prevents the chain from extending beyond horizontal, and has the effect of limiting the chain's bending motion to a number of adjacent links.

I liked ld3300's revamp of an already great design, but there were some inconsistencies in the model that needed to be cleaned up. There were some internal surfaces left over from when the additional elements were merged onto johnniewhiskey's model. This had the effect of printing a seam within the link that eventually caused it to separate into its component parts.

I fixed any duplicate edges, removed additional faces internal to the model, and cleaned up the vertices to ld3300's original blender file and reproduced the STL. I believe this represents the originally intended model and should be free of any printing defects.

ld3300 -- Thanks for the great idea to modify the existing Ender 3 cable chain. I'm using this in my build. :D